This video helped me so much! I broke a rare cannondale frame last year. Thanks to your guide, I repaired my frame and rode over 4000 miles on my favorite bicycle! No issues, even riding HARD, with lots of gravel.
Jim gets the Oscar for best carbon repair. I crashed my Roubaix and trying to learn how to repair my bike. For a week I’ve watched all the carbon repair videos. Jim is the best. He gave me enough confidence to jump in. Thank you Jim.
My pleasure Chett - and thanks for making my day with your great comment! If you go ahead with your repair please share how it goes so other viewers can learn from you. Thanks a lot for watching and the awesome comment, appreciate it!
As a former stress analyst the procedures for relate of aircraft composite structure requires complete removal of damaged material. Composites with voids or fractures internal tend to eventually fail which is why the X-ray or use ultrasonic testing to verify structural integrity. Covering a fracture is covering a void. Graphite fibers at very brittle, stiff and strong in tension. They have virtually no compressive strength unless supported by the matrix due to the fineness of the fiber they buckle under compression and fracture. This fracture tends to proprogate with many cycles then the member will suddenly fail. Composites without defects can have virtually infinite fatigue life but unsupported fibers tend to buckle. If the member is highly loaded it is best to sand out all damaged material then try to duplicate the layup or more likely do 0/45/90/-45 layers and over build it. It is difficult to do a proper repair that is invisible because you need over lap to develop the load trough inter-laminar shear. You could probably get away with a collar over the damage if you really over build it but best practice is to remove all damaged matrix and fibers. Brian Blum
I was browsing RUclips when this video produced a year ago has been attracting some attention. Firstly well done if you going to have a go to save money. I mean that. We hate waste and more importantly safe repairs are even more important. What constitutes a safe repair you may ask? In the case of very thin light carbon bikes- consistency with in the construction. Why? Because thin light bikes rely on the asymmetrical characteristics to share load. Remember these bikes are built to the absolute minimum in materials they deem correct for the function of the particular bike. The big difference between the method you see in this video and a professional repair (I say this with caution as not all are professional repairers or indeed know the correct method for some parts) is that the repair is reconstituted, undetectable carbon composite of the same thickness density and profile. Change that and your repair is not in harmony when under load. Beside this point the approach to each location of a fracture can vary in process and indeed materials. If we were talking 10 years ago this wouldn’t be completely valid but with todays bikes which are a great deal lighter the emphasis on consistency is paramount. We have robots now which emulate molds and repair precisely because even the most skilled repairer cannot honestly guarantee the wall thickness and densities are correct. So to conclude in the name of your safely: if you repair a carbon bike it could be a bit safer on very old carbon or very cheap heavy carbon bikes where mid tube fractures exist on the top down tubes and the 4 stays otherwise frames under 1kg you risk yourself or someone else’s life. Rob Granville, CarbonBikeRepair
Thankyou for this. I dont ride a bike but my wheelchair is carbon fibre and i bought a second as a spare knowing it was heavily reduced due to a crack in the backrest and thankfully i ended up being able to switch the backs over so i have one fully functional chair but i wanted to have a go at fixing the crack so started by filling in some chips and dings first, this really did uelp inspire some confidence and ive just unwrapped the carbon fibre repair today! My brother (car fan) says id need a few more layers of expoxy over the repair but im not sure how id go about that? I do have some of the clear tape left but have been sanding it smooth today. Its part of a backrest so semi weight bearing id say. But impressed so far! Thanks for posting this!!!!
You're very welcome! Thanks for watching and commenting. I'm so happy the video helped you with your carbon fibre wheelchair repair and congratulations on doing it yourself. In regards to adding layers of epoxy, as I understand it, it's the carbon that adds the strength not so much the epoxy. I believe you'd want to add more carbon layers to add strength. Thanks again!
Hi Jim, I dropped my bike this evening and as a result I have cracked the frame, I went on the predator website, but I could not see the kit for sale… is the ram alternative, I live in the UK
Not witchcraft although the bike industry would like you to think so. People repair boats like this. I'm 100kg and I have done a downtube near bottom bracket like this. Good vid.
I've got a crack in my carbon frame in almost the exact same spot, also from falling over. I don't really want to do this, but it's probably better than any other solution sans buying a new bike - which I want to, I just can't afford what I want at this moment.
Thanks for watching and commenting Sean. The kit is $100 so it's much cheaper than a new bike 😊and the repair isn't that difficult. The only hard thing is repainting the repaired spot, which I chose not to do. But other than that, it's straight forward.
Excellent video. I repaired a Giant TCR Comp bottom bracket shell. Bottom on the chain stays side was shattered. I rode that bike 9 more years. I thought damage was from a crash I had but I think they had a recall on that frame (2003/2005).
Hi Jim - if the crack in the frame is on one side, do you think I need to go all of the way around the frame? Or would it be enough to just cover the damaged area?
Thanks for watching and the question Karl. I used a kit for this repair that I bought from Predator (the link is in the description). I took a photo of my frame and sent it to them first to make sure their kit would work for my frame damage. You might want to do that just to get a professional opinion from a company that repairs carbon frames. I wouldn't want to give you the wrong advice because damage to carbon can be challenging to evaluate from looking at it. It might be that the crack is so minor it doesn't need a full wrap but it might also be that there's more damage that you can't see. Companies that fix carbon bikes X-ray them to see how badly these cracks are. If you wrap it fully you won't be taking any chances but maybe Predator will say it's fine to only cover the crack.
Fantastic video, thank you! I appreciate your DIY ethos, and share it as well. While interested in CF bikes, I am very wary of hidden frame damage on used bikes more than any other frame material. This is what is holding me back, as well as new bike prices, which I find increasingly ridiculous!
Glad you enjoyed the video, thank you for watching and commenting. Carbon is actually super strong. It takes very specific types of damage to crack or break it such as how my top tube landed on a pointed rock. The good news is that there are carbon companies that can X-ray carbon frames to inspect them and ensure there's no hidden damage. So if you found a used carbon bike at an affordable price point you could have it inspected to put your mind at ease. Hope this is helpful and thanks again!
i was looking for a video on how to remove small scratches from carbon wheels and look what i found. bad luck you had with your bike Jim. the repair looks good. i think the pain is if you try to paint and find the right colors, etc.. perhaps a big stricker somehow would help., btw , now that im here, do you know by chance, how to remove small scratches from a matt carbon wheel? thanks
Thanks for watching Gledii! I did pretty much what you said and just covered the repaired area with electrical tape. It's not as pretty as the paint job I removed but it protects it just fine and it makes it easy to remove the tape and show the repair if anyone asks about it. To paint it correctly to match the original finish is beyond my skills with paint. And I don't feel it's worth it to have the frame repainted by a professional. As far as removing scratches from matte finishes, I think you'd want to reach out to or watch some RUclipss from the car repair or car restoration people. I couldn't find anything very helpful searching a bit. Most of what I found says that the problem is if you try to buff or polish it out you will turn your matte finish into a gloss finish. Which makes me think you need a product to touch up the scratch with the same type of matte finish you have now. Sorry I can't help any more but painting and finishing is its own art. If you find something that works please share what it is. Thanks again and good luck!
@@Gledii I washed my bike yesterday after a really muddy ride and my carbon wheels have some pretty good scratches too now after thousands of great miles, so I know what you mean by no big deal 😊
really useful to see each step! many thanks - I just found a small hole caused by a bottle mounted in the seat tube hitting the down tube - as the bike rattles down trails the base of the bottle was hitting the tube and eventually put a small puncture in it. I'll repair it and your video gives me the confidence to try! THANKS!
what strikes me is how fragile such frames are. The properties of carbon fiber being stronger than metal are clear, however, in case of impact, Aluminum and iron would only dent. This repair seemed visually ok, im wondering if you measure the true strength on the tube if it will be strong enough only with these 2 layers of carbon fiber. thanks for sharing
Thanks for watching and commenting, appreciate it. Carbon actually is super strong but like all materials it has its weaknesses such as sharp objects and sufficient penetrating force. I don't have a way to measure the strength of the repaired tube other than riding the bike. I have ridden it a ton since the repair and it rides and performs as it did before the break. The way to look at the repair is not as just 2 layers of carbon fibers but all the layers that were in the frame already PLUS 2 more layers on top, so it should be even stronger than it was when new. Hope this helps explain more, thanks again!
@@JimLangley1 this make sense. im sure the tube around the crack is even stronger, i was just wondering exactly where the crack is. Ive seen dropbars delaminating and breaking like glass when pressure was added to a crack (under the tape). thanks for sharing
Thanks for watching Roberto! The specs on the carbon provided are: 5.8oz - 3K, 2x2 Twill Carbon Fiber Fabric Weave, 6 in x 12 in Predator doesn’t say how thick it is but I would estimate 3mm. You can buy the carbon from them. Hope this helps and thanks again!
Nice video! I was a little surprised how much the kit cost, though that's cheaper than getting it repaired by a professional. Repairs of the sort seen here are not 1K but more around 300-400$
Great video, thanks for sharing. I have a Canyon Ultimate with a cracked top tube, quite substantial and covers about 60-70% of the circumference, localised to a single area luckily, do you think it is safe to use this kit to repair it? Thanks for your help in advance.
Thanks for watching and the question. It sounds like you have damage that's similar to what I had on my Cervelo, which makes me think the kit will work for you. You can also contact Predator and discuss your frame damage with them to see if they agree as they are the carbon experts. If you use it to repair your frame, please let me know how it works. Thanks again!
@@JimLangley1 Thanks for the prompt reply! I will definitely get in touch. I am also looking at using unidirectional carbon fibre and the hassle of layering it in different direction. I am still researching so could go either way...
Thanks for watching and the question Chas. It looks like they changed the link. Here it is: predatorcycling.com/products/carbon-repair-kit Thanks again!
Thanks for watching and the question, Chris. The dropouts on carbon frames are completely different than the tubes like what I fixed with the kit in this video. Dropouts are solid parts made with molds not hollow parts like carbon frame tubes. If dropouts wear out or break you need to replace them with a new dropout because if you try to glue another solid carbon piece to what's left of the dropout it'll break off. So to fix that frame you should find a carbon bike frame repair company you can bring it or send it to because they'll have replacement dropouts and be able to properly install it in your frame to make it ride like new again. Here's one such company calfeedesign.com/carbon-repair/ Hope this helps.
How is the repair holding up Jim ? I can't see any comments on the final use of the bike. I was trying to figure out how long ago you did the repaired . Please advise, thanks.
Thanks a lot for watching and the question, Jo. I did the repair in August of 2022, so it's been 4 months of riding on it so far - about 1,000 miles on that bike with a lot of steep, long climbs here in the Santa Cruz Mountains. And it's been holding up just fine. I have not put anything over the patch yet which makes it easy to look at it and feel it to see if it's changing in any way and I haven't noticed any change at all. It's recommended to wrap it with electrical tape or paint it so as to keep the UV rays from affecting it and I'm going to do that soon. Right now all it's doing here is raining - we need it, too. Thanks again for watching and commenting. Hope this is helpful!
I observed a crack in the seat tube of a Pinarello Prince SL (my dream bike at the time) soon after I bought it from a fellow who had at least 10 other Pinarellos hanging from the walls inside a room in his home. (Another room had as many Stratocasters.) (Guy obviously had more money than sense.) (On the other hand, who needs sense? He had a stunning 19-year-old girlfriend - he was probably in his 40s - and they were about to leave town to jet off to San Diego because they had heard the surf was up.) I asked him why he was selling and he said that he never rode this one. (I subsequently discovered the odometer showed he had put 10,000 miles on it. I suspect that this was his go-to ride until he cracked the frame somehow.) Word to the wise - buying a bike from a stranger for a price that seems too good to be true - check the frame over with a fine-tooth comb. Live and learn. Sorry, I digress. Being stubborn, I rode the bike for a year until a bike mechanic finally pulled me aside and told me I was flirting with catastrophic failure and likely certain death. (Tell the truth, I had been using this bike to crawl up and barrel down Red Mountain Pass in Colorado.) So I was left with the question of how to tell whether it was a superficial crack in the paint (what I had tried to tell myself it was) or a structural crack in the tube? I didn't try the coin tap (I actually tried it just now because I still have the frame - it didn't work - but I think my frame at this spot is aluminum, not carbon). So I thought I'd post what I came up with since it worked like a charm. Paint the outside of the crack with dish-soapy water, plug up all the holes in the frame, put the hose of a bike pump in a hole (plugging the space around it) and pump. Good news was, my idea worked. Bad news was, the crack blew bubbles like Spongebob Squarepants. (I promptly bought a Moots titanium frame with a lifetime guaranty, transferred over all the components, which were first class, and I'm still riding it 20 years later - all's well that ends well.) Anybody know how to fix a crack in an aluminum frame? Maybe a carbon patch like this would work.....
Wow, great story Citizen, thanks for telling it and for sharing the cool way you determined that your Pinarello was cracked and not just scratched/chipped - well done! As for how to fix an aluminum frame that should be a relatively easy fix for a bike framebuilder who works with aluminum. Here in Santa Cruz, California rocklobstercycles.com could probably do it for you.
Be interesting if the ride characteristics of the frame changed after stiffening it up in a flex section or if you could even notice. Masking tape doesn’t like excessive heat
Thanks for watching and the tip about not using masking tape to mask the frame off jonny, appreciate it. I do not feel any difference in stiffness but that's a subjective thing to feel and usually related to the size of the rider and their strength so another rider might. Thanks again!
Thanks a lot for watching Patty, glad you enjoyed the show, appreciate you commenting. I checked the Predator website and I still see the kit here: predatorcycling.com/products/carbon-repair-kit
@@JimLangley1 Oh now I see... obviously only available within the US. Got a "page not found" from Germany and with a few other countries I tried, choice for that is all the way at the bottom of the page.
Hi, this is a great video. I have a similar crack on my bike. Bit less of a crack but more of a bruise if you like. I have been not riding for a while but want to get back on it and want to fix it before. This video gives me confidence that I can do it myself. Also I thought the coin was Australian $2 but reading the comments realized it is euro. Thank you the video.
Thanks a lot for watching, glad you enjoyed the video Purvag. It’s a pretty straightforward process and the folks at Predator that sell the patch kit are very helpful if you need any.
Your video is inspiring me to fix my carbon bike that’s been sitting in the closet for years. I hit a car head on, snapped my fork but didn’t notice the crack until I went to the bike shop. The crack I have starts from the top of head tube and goes down about a centimeter. Now I know you might be more of a novice to carbon repair, but you seem to have some good knowledge about bicycles. Would you have confidence in this kit for a small crack in a head tube? I think I’ve been told repairing carbon there is a bit more risky. Thanks!
Thanks a lot for watching and the question James. I'm glad my video has inspired you to try to fix your frame, but a crash with a car that breaks a fork is a major impact and it's impossible to know how badly your frame might have been damaged just by looking. That crack that you see might just be the tip of the iceberg so to speak.. with more damage inside the carbon that isn't visible to the eye. So, I would recommend you take the frame to a company that x-rays carbon frames to check for damage to the carbon. That way you can be certain that it's only that small crack and not structural issues in other parts of the head tube that could lead to a catastrophic failure later. I don't know where you're located but you can find carbon bicycle repair places in different parts of the USA that can do this and also in Europe. It shouldn't be too expensive to just have it inspected and you'll also learn how easily it'll be to repair the frame. I hope this helps and you can get back out on that bike. Good luck.
Is the carbon fiber patch overlapped when you wrap it around the tube or end it evenly. I would think that overlapping would give the repair the maximum strength.
Yes I saw that the two patches overlap each other. My question is do the individual patches overlap themselves. When I wrap patch one around the frame does it overlap itself on the bottom? And when I wrap patch two around the frame (over patch one) does patch two overlap itself on the bottom. FYI, I have a cracked seat stay from the bike falling over sideways on a curb and I have ordered the Predator kit that you suggested. Thanks!!!
@@DaveIngels-x6d on my repair which was a top tube - pretty large diameter tube - the smaller patch did not need to overlap in my judgment but the larger patch that completely covered the smaller one did to join its ends and fully encircle the patch underneath and the whole tube. I basically followed the instructions in the kit. For a stay, which is smaller diameter I think you might want to overlap the patch ends on both patches. I’m not 100% sure though. I think you should call Predator and ask to see how they would do it. I called them and they were very helpful. I had to call a couple times but I did get to speak to a tech guy when I got hold of them. Better to speak to an expert first before committing. Hope this helps and have fun fixing your frame.
Thanks for watching, glad you enjoyed the video greaserleo. The kit I used provided the epoxy and hardener in a 2 to 1 ratio. The container of epoxy was 4 ounces and the hardener was 2 ounces and the directions have you mix them together fully. You can see the epoxy and hardener here: predatorcycling.com/products/epoxy-resin-and-hardener Hope this helps and thanks again!
Thanks for watching and the question vb. I have two Treks and both are great-riding bikes so I think you'll love your FX. It's actually made of Trek's OCLV carbon (Optimum Compaction Low Void). They've been refining and improving their OCLV carbon frames for decades now and there's a lot to know about it. You can learn more about it at this webpage on their site - they might give the tensile strength there www.trekbikes.com/us/en_US/inside_trek/oclv_carbon/ Hope this helps and let me know how you like the bike if you get it!
You're welcome Andy and thanks for watching. Heat guns differ in how much heat they put out and moving them closer or further away changes how intense the heat is too. What your goal is is to get the heat shrink tape to shrink. You can see in my video that at first the heat gun has no effect and the tape won't shrink. As the heat gun stays on a little longer it gets hotter and I move the hot air a little closer and at that point you can see that the shrinking starts because the resin/epoxy starts getting squeezed out in between the tape. So basically it's by trial and error how you figure out how hot it needs to be and how close you hold it. But you go little by little - a little more heat, a little closer until you see it shrink. Here again you could put a piece of tape on the workbench and heat it up as a test to learn what setting on your heat gun and how close to hold it to get the shrinking to happen. That would give you an idea what it's going to take on your frame repair. Hope this helps.
Happy to hear you found the video helpful Tom, thanks for watching and commenting. It’s not that difficult a repair, you can do it. Yeah my first car was a Bug and I’ve had VWs most of my life. Our Westy has been great. Never owned a GTI but drove my brother’s - super fun - just gotta watch for cops😊
Thanks for watching and the comment, JogBird. It's basically the same process used by frame repair companies so it should work fine. Predator Cycling offers great support, too. You can discuss with them whatever you're trying to fix and they'll tell you if their kit will work for it.
@@JimLangley1 The only thing I wouldn't use it on is a fork since that is unsupported and very safety-critical if it does fail. Nice repair and I'd be very surprised if it doesn't hold up! Repainting tricky because of the pattern. Maybe have a look at the ETOE channel and respray the whole frame in an interesting colour scheme :)
@Ben C thanks for watching, Ben. I broke a carbon fork once and it wasn't fun at all 😊. Thanks for the tip about the ETOE channel, that guy has done some impressive paint jobs! At this point I'm still thinking I'm going to cover it up rather than repaint. But it's great to have such a helpful resource, thank you!
Thanks for watching and the question Andy. It's been over a year now and I haven't had any problems at all, the repair is holding up just fine. Thanks again!
You could put it in a sunny small room that gets warm or turn the heat up in your house and put it in the smallest heated room near one of the heat vents but not on top of the heat vent. And you just wait until the resin has dried, turned hard. You can put some of the resin you mix on something and leave it to dry and check this to see when the repair should be dry. The resin will cure even if you don't keep it in a warm room but when it's warm the resin dries faster that's all.
Honestly didn’t even knew this could be possible, so thanks for sharing!!! Only one comment, UV rays degrades/decay Carbon Finer some kind of paint would help a lot to preserving it
Thanks for watching and I'm happy you enjoyed learning it's possible to repair carbon bikes, dranenko. I think you missed the part where I talk about covering up the patch to protect it from UV rays. That's at 14:44
Thanks for watching and commenting, Robert. If you have any questions about your frame and the problem you're fixing you can reach out to Predator - the company that makes the kit and they'll walk you through it. And the kit comes with pretty easy to follow instructions. Hope this helps!
Hi, very nice repair vid! I have a crack around my front derailleur mount bracket - which was pop riveted and bonded in place, but had come loose. Crack is longitudinal, 2-3 inches long. Someone must have banged the derailleur into something. Will I need to wrap the repair material all 360 around the frame, or only over the crack + some side overlap? Also, what is the thickness of the repair patches?
I'm glad you enjoyed the video Soren, thanks for watching and commenting! Your frame is cracked in a highly stressed area and that derailleur mount being pop riveted there complicates matters. I'm not sure you'll be able to fix this with a kit like the one I purchased from Predator (link to the company is in the description). I think to be safe you should take some photos of the damage and reach out to Predator or another carbon company to get their advice on whether you can fix it with a patch or if it needs a more extensive analysis (they can x-ray the frame) and sophisticated repair to deal with the frame and the front der. mount. Hope this helps and thanks again!
Thanks for watching, Carlos! I'm sure it'll hold up - it's the same process basically that professional carbon repairers use - and I'm definitely looking forward to riding thousands of more miles🙂
@@tariusvadoom6489 thanks for watching and asking, tarius. The patch is holding up fine, no issues at all after hundreds of miles and thousands of feet of climbing the longest steepest climbs here.
Really cool video, the repair looks super strong. I watched some other videos where they put the carbon fiber on, and paint on top after instead of pre-painting. Any reason why you pre-applied epoxy?
Thanks for watching, Denis, the repair has been holding up great so it does seem super strong. The reason I applied the epoxy like that is just because that's the way the instructions in the kit said to do it and I wanted to follow their step by step to be sure to prepare and apply the epoxy, frame and patch according to their procedure. For the patches the epoxy goes on first so that you can flip them over and apply it to both sides of the patches. It definitely was a lot of epoxy and I probably could have used less and it would have been fine. Thanks for the great question!
Got mine fix for 300. By a professional. And they scanned the bike to see for other cracks. And painted it to match the old paint. It was black so pretty easy 😂 it was cracked all the way through though
Great job Jim! I have a similar crack but it’s on the bottom stay of the rear triangle of a Specialized mountain bike - I’m wondering if a repair of this sort would be durable enough for a bike designed for a lot of aggressive riding
Glad you enjoyed the video Rossi, thank you for watching and commenting. Chainstays are usually pretty heavy duty so I think this repair would work well for your frame. The company that makes the kit is happy to look at photos and advise if the kit can fix the crack you have too. So you could ask them to take a look to make sure. Hope this helps and that you can fix it.
I didn't use a certain temperature, I just made sure it was warm around the frame probably 75 degrees. You might want to watch the 2-part video that Predator Carbon made to show how to use their kit. Here's part 1: ruclips.net/video/tS7y6rZvBeo/видео.htmlsi=fRBF2NIn3wv3pZB_ And here's part 2: ruclips.net/video/0OZxeGNnSIU/видео.htmlsi=H8mlloaVuzsHao-1
Used the same idea for repairing nordic ski poles. But this kit appears overpriced at $100, unless the carbon tape is of particularly good quality. I had a head-on collision on my trek Madone. The fork snapped, and I have replaced it. The bike rides "fine", but I am paranoid whether the frame also has cracks that I cannot see. I wonder if there is a way to reveal these small cracks (better than a coin). Don't wanna wrap each tube "just in case" :)
Thanks for watching and commenting, appreciate it. Yes, you can have your bike x-rayed to determine if the tubes were damaged in that head-on crash. Here's a website of a company not too far from me here in Northern California that does it for example: www.spydercomposites.com/ There's probably companies like this in other areas of the USA too. You could google "carbon bicycle repair" Hope this helps and thanks again!
Thanks a lot for watching Joseph, glad you enjoyed the video. I think you should reach out to Predator Cycling the company I bought the repair kit from. Maybe they sell the compression tape or know where you could buy it. If you find a source please let everybody know in a comment. Thanks!
Thanks for watching and the question Ronnie. I use a carbon repair kit I purchased from Predator Carbon. There's a link to in the description and it's shown early in the video.
Thanks, Zer0, appreciate it! I have been too busy to find the right color tape and everybody keeps wanting to see the patch 😀 so for now it’s still unfinished. But I will see if I can do a nice tape finish sometime soon I hope. Thanks again!
@@jacksobe thanks for checking out the comments to find the answer jacksobe, appreciate it! I did two climbing rides on that bike last week and it's working great.
Awesome video, how is the frame holding up? My bike shop just found a crack on my seat tube, I'd love to save $ doing it myself, but I'm not sure it'd be safe/sustainable since the tube holds so much more weight. Any thoughts?
Thanks for watching, Paige, glad you liked the video! My repair is holding up just fine. I haven't had any issues at all and I've ridden the bike a ton. For your issue, the very first thing I'd do is to find out if your frame is covered by a warranty - most frames are. I would think the shop would have thought of that straight away but in case they didn't that's the first and best way to deal with it because the company that made the frame knows the most about their frame material, design, etc. and if it broke they might replace it under warranty. I know people who are on the second even third frame this way. If that's not an option, you might at least learn from the company whether the damage is repairable. If you want to do it yourself, take a photo of your frame crack and reach out to the company that sells the repair kit I used predatorcycling.com/products/carbon-repair-kit They'll look at your photo and tell you if the kit can fix the crack you have. Hope one of these options works and you can save that frame or get one under warranty.
Hey thanks for watching and the great question Ikarim - I wondered if anyone would spot the coin I used. I used it only because it looked better on camera and it’s thicker than a quarter- and yes I’m in California. Thanks again for watching, glad you enjoyed the video!
Thanks for watching and making this point Stephen. A steel frame subjected to what happened to my carbon frame would just get dented, it wouldn't crack. You could keep riding both frames. The dent in the steel frame wouldn't be likely to change. It would look ugly but the tube probably wouldn't ever crack or fail. The crack in my carbon frame would probably have grown larger over time and might have continued all the way around the tube causing it to break.
@@JimLangley1 Agreed. Personally, I'm still of the view that steel is an excellent material for bicycle frames. It's strong, tough, and resilient. Cheers.
Removing paint with a razor blade is fine with steel frames since the blade can’t cut into steel. But it can cut carbon. That’s why you use sandpaper. Yes, it’s slow but it lets you remove the paint carefully and not risk damaging your frame any more than it already is.
@Jim Langley mate the blade doesn't touch the carbon it slides once you reach the carbon layer and you can see no more white ish lacquer flakes coming off,I've been professionally repairing frames since 2009 and come fram a composites back ground, at the peek I was doing 10 frames a day and you need at that point to find fastest way to achieve your goal
@@guinnesslover2970 appreciate you sharing your expertise and tips. My concern is that this kit is for beginners and comes with and says to use the included wet sandpaper. Also cracked carbon frames and rims, etc can cut you if you’re not careful. I wouldn’t want someone sliding a blade across a tube to run into the crack and splintered carbon. But I believe an expert like you can do it and I am sure it’d be a lot faster. Thanks again.
Thanks for watching and the tip guinnesslover. When trying to get the ratio of epoxy to hardener right you can end up with more than you need. The compression (shrink) tape and heat squeezes out the excess resin.
Thanks a lot, David, appreciate you watching and commenting! Yes, it was lucky the break was there and their shrink tape was truly ingenious and pretty easy to use, too. I love my steel bikes, too😊 Thanks again!
Respectfully, I don’t think that frame can be fixed. I feel like that’s a catastrophic failure waiting to happen with a bandage on it . For me, the only way to fix a carbon fiber frame is to have a good steel frame.
Frames are built with ~4 to 8 layers of carbon depending on where the strength is needed. DO NOT patch your bikes like this. There's a reason why it costs so much to patch a frame. They put more than 20 minutes and 2 bandaids into the repair.
Thanks for your opinion bentBuilder but this repair took hours and the frame now has its original layers plus 2 more. It’s a kit designed and made by a carbon frame company and they confirmed it was correct for my frame damage. I have many many hard miles on the frame now and it’s fine. Carbon is much stronger than it might seem.
Hello Jim. I hope you are aware that this is a replacement repair that does not guarantee the transfer of loads like the original. After such a repair, there are many dangers, which the strength of the materials speaks of. I will just mention that the cross-section of the same piece is different than that of the base element, there is still a notch there and there is a large material fault, which may cause bending stresses. In addition, there is a high randomness of execution, no tests and no control after repair beyond the control of the coin :). Generally it is very risky what you did, but .... whereas you are a sensible person with experience as a bicycle mechanic, you have all the risks at the back of your head. I recommend not to paint this bypass and make a visual inspection after each ride to see if there is a crack. On the other hand, the rupture of such a thin patch will be very violent and rather total. Apart from the topic, I am a little surprised people buy a product as risky, poorly made, dangerous and easy to damage as carbon bicycle components. In my case, I only have a carbon water bottle cage, which may also do some harm in the event of a breakage. Best regards and good luck with this frame.
Thanks for watching and for your thoughtful reply Michal. I appreciate your concern for my safety. I probably should have explained more about the patching in the video. I'll do it here to try to address and ease your concerns. I bought the patch kit from Predator Cycling, a company that manufactures carbon frames and I first discussed my repair with them and showed them photos of my frame's crack. They told me that their kit was made for these types of repairs. The way the repair works, the carbon patches saturated with epoxy are pressed hard onto the sanded and cleaned carbon of the frame with the heat shrink tubing. During the process of drying, the carbon patches and carbon frame become one. The carbon patch presses down into any groove remaining where I sanded the crack. So, if it all worked as designed, that area of the frame is now 2 more layers of carbon thick and the crack - at least on the outside of the frame should be completely filled and reinforced, too. Thanks again!
I've got to disagree, there are no dangers the more overlay of carbon the stronger it becomes, I've repaired lots of mtbs in a similar manner, even chain stays and they are bullet proof, there's no way that would continue cracking or break, its alright saying this will happen and that will happen when you've never experienced doing a carbon repair, or not really knowledgeable about it, it's no different from welding a hole up in a piece of steel, it's just a bike it's not under serious load, people like you worry about the smallest things 😉 that frame will be solid
@@shaunsmith3660 Thanks for the comment, but I definitely disagree with you. The fact that you have repaired a hundred frames and they are still alive does not mean anything. If you had any knowledge on this subject, you should know what the fatigue calculations look like. I am referring to the material strength course, especially please pay attention to the section devoted to fatigue analysis.
@@mutos82 I can see you you are ignorant and clearly never done a carbon repair in your life, you stick to your figures and calculations on that piece of paper or screen and let the big boys fix stuff 😉
It is not as good as prepreg + autoclave/rtm (as it is made at the bike manufacturer) due to small compression, not optimal epoxy to carbon ratio (more epoxy = more fragile) and possibly there could be air bubbles/voids in the laminate (not this case as it seems, but usually it comes with diy aproach)
@@Anton-zb9dc thanks, Anton. This is a kit that comes from a maker of carbon bicycles, so you're getting what they designed to fix cracks, i.e. what a professional carbon manufacturer recommends and that includes the carbon fabric, the epoxy and hardener in exact measurements and how to mix it (no bubbles) and how to compress it - in a different way than a mold is used but still very effective. But I can see how if you didn't use a kit and tried to figure out how to buy the materials and do it yourself you might not end up with a proper repair. But with this kit, you'd have to not follow the directions or make a major mistake.
It would be cool if you would inspect the repair from inside with endoscope to see if there are any drips of epoxy or something similar. That would be interesting!
Thanks for watching and commenting, theresnobody! Actually I've "had the pleasure" of breaking multiple frames and it can be a lot more pain than pleasure when you hit the deck, ha, ha 😆
![I.N "HALLUCINATION" | [Stray Kids : SKZ-PLAYER]](http://i.ytimg.com/vi/n5B5q1Hwt_U/mqdefault.jpg)
★ WATCH this video next where I true a crashed carbon aero wheel ruclips.net/video/NyPGQrNfUFU/видео.html
This video helped me so much! I broke a rare cannondale frame last year. Thanks to your guide, I repaired my frame and rode over 4000 miles on my favorite bicycle! No issues, even riding HARD, with lots of gravel.
That's great to hear Big, thanks a lot for letting me know and congrats on fixing your C'dale! Appreciate you watching and commenting!
Jim gets the Oscar for best carbon repair. I crashed my Roubaix and trying to learn how to repair my bike. For a week I’ve watched all the carbon repair videos. Jim is the best. He gave me enough confidence to jump in. Thank you Jim.
My pleasure Chett - and thanks for making my day with your great comment! If you go ahead with your repair please share how it goes so other viewers can learn from you. Thanks a lot for watching and the awesome comment, appreciate it!
As a former stress analyst the procedures for relate of aircraft composite structure requires complete removal of damaged material. Composites with voids or fractures internal tend to eventually fail which is why the X-ray or use ultrasonic testing to verify structural integrity. Covering a fracture is covering a void. Graphite fibers at very brittle, stiff and strong in tension. They have virtually no compressive strength unless supported by the matrix due to the fineness of the fiber they buckle under compression and fracture. This fracture tends to proprogate with many cycles then the member will suddenly fail. Composites without defects can have virtually infinite fatigue life but unsupported fibers tend to buckle. If the member is highly loaded it is best to sand out all damaged material then try to duplicate the layup or more likely do 0/45/90/-45 layers and over build it. It is difficult to do a proper repair that is invisible because you need over lap to develop the load trough inter-laminar shear. You could probably get away with a collar over the damage if you really over build it but best practice is to remove all damaged matrix and fibers. Brian Blum
Appreciate you watching and educating us Brian, thanks a lot! 🙏❤
I would over build it on the inside leaving the outside nice, inserting some foam on the inside to compress against
I was browsing RUclips when this video produced a year ago has been attracting some attention. Firstly well done if you going to have a go to save money. I mean that. We hate waste and more importantly safe repairs are even more important. What constitutes a safe repair you may ask? In the case of very thin light carbon bikes- consistency with in the construction. Why? Because thin light bikes rely on the asymmetrical characteristics to share load. Remember these bikes are built to the absolute minimum in materials they deem correct for the function of the particular bike.
The big difference between the method you see in this video and a professional repair (I say this with caution as not all are professional repairers or indeed know the correct method for some parts) is that the repair is reconstituted, undetectable carbon composite of the same thickness density and profile. Change that and your repair is not in harmony when under load. Beside this point the approach to each location of a fracture can vary in process and indeed materials. If we were talking 10 years ago this wouldn’t be completely valid but with todays bikes which are a great deal lighter the emphasis on consistency is paramount. We have robots now which emulate molds and repair precisely because even the most skilled repairer cannot honestly guarantee the wall thickness and densities are correct. So to conclude in the name of your safely: if you repair a carbon bike it could be a bit safer on very old carbon or very cheap heavy carbon bikes where mid tube fractures exist on the top down tubes and the 4 stays otherwise frames under 1kg you risk yourself or someone else’s life. Rob Granville, CarbonBikeRepair
Thanks for watching and for sharing your expertise Rob, appreciate it. 🙏
I heard some great comments about CBR… very happy customers.
Thankyou for this. I dont ride a bike but my wheelchair is carbon fibre and i bought a second as a spare knowing it was heavily reduced due to a crack in the backrest and thankfully i ended up being able to switch the backs over so i have one fully functional chair but i wanted to have a go at fixing the crack so started by filling in some chips and dings first, this really did uelp inspire some confidence and ive just unwrapped the carbon fibre repair today! My brother (car fan) says id need a few more layers of expoxy over the repair but im not sure how id go about that? I do have some of the clear tape left but have been sanding it smooth today. Its part of a backrest so semi weight bearing id say. But impressed so far!
Thanks for posting this!!!!
You're very welcome! Thanks for watching and commenting. I'm so happy the video helped you with your carbon fibre wheelchair repair and congratulations on doing it yourself. In regards to adding layers of epoxy, as I understand it, it's the carbon that adds the strength not so much the epoxy. I believe you'd want to add more carbon layers to add strength. Thanks again!
Hi Jim, I dropped my bike this evening and as a result I have cracked the frame, I went on the predator website, but I could not see the kit for sale… is the ram alternative, I live in the UK
Sorry to hear you cracked your frame Alistair. Here is the link to the kit predatorcycling.com/products/carbon-repair-kit Hope this helps!
@@JimLangley1 many thanks Jim, much appreciated,
Not witchcraft although the bike industry would like you to think so. People repair boats like this. I'm 100kg and I have done a downtube near bottom bracket like this. Good vid.
Thanks for watching and for making this point Nicky, appreciate it, and congrats on repairing your carbon bike too! 👍
I've got a crack in my carbon frame in almost the exact same spot, also from falling over. I don't really want to do this, but it's probably better than any other solution sans buying a new bike - which I want to, I just can't afford what I want at this moment.
Thanks for watching and commenting Sean. The kit is $100 so it's much cheaper than a new bike 😊and the repair isn't that difficult. The only hard thing is repainting the repaired spot, which I chose not to do. But other than that, it's straight forward.
Excellent video. I repaired a Giant TCR Comp bottom bracket shell. Bottom on the chain stays side was shattered. I rode that bike 9 more years. I thought damage was from a crash I had but I think they had a recall on that frame (2003/2005).
Nice job rcdogman! Thanks for watching and for sharing your Giant carbon frame repair!
Hi Jim - if the crack in the frame is on one side, do you think I need to go all of the way around the frame? Or would it be enough to just cover the damaged area?
Thanks for watching and the question Karl. I used a kit for this repair that I bought from Predator (the link is in the description). I took a photo of my frame and sent it to them first to make sure their kit would work for my frame damage. You might want to do that just to get a professional opinion from a company that repairs carbon frames. I wouldn't want to give you the wrong advice because damage to carbon can be challenging to evaluate from looking at it. It might be that the crack is so minor it doesn't need a full wrap but it might also be that there's more damage that you can't see. Companies that fix carbon bikes X-ray them to see how badly these cracks are. If you wrap it fully you won't be taking any chances but maybe Predator will say it's fine to only cover the crack.
Fantastic video, thank you!
I appreciate your DIY ethos, and share it as well.
While interested in CF bikes, I am very wary of hidden frame damage on used bikes more than any other frame material.
This is what is holding me back, as well as new bike prices, which I find increasingly ridiculous!
Glad you enjoyed the video, thank you for watching and commenting. Carbon is actually super strong. It takes very specific types of damage to crack or break it such as how my top tube landed on a pointed rock. The good news is that there are carbon companies that can X-ray carbon frames to inspect them and ensure there's no hidden damage. So if you found a used carbon bike at an affordable price point you could have it inspected to put your mind at ease. Hope this is helpful and thanks again!
I enjoyed watching your video and now I learned something new. Watching from the Philippines
Thanks a lot for watching and the great comment Niegel, appreciate it very much!
Thanks Jim ! Very instructive video !
You’re very welcome Pier, thanks for watching and commenting!🙏
Thanks a lots lots 👍👍
My pleasure Elmer, thank you for watching and commenting!
i was looking for a video on how to remove small scratches from carbon wheels and look what i found. bad luck you had with your bike Jim. the repair looks good. i think the pain is if you try to paint and find the right colors, etc.. perhaps a big stricker somehow would help., btw , now that im here, do you know by chance, how to remove small scratches from a matt carbon wheel? thanks
Thanks for watching Gledii! I did pretty much what you said and just covered the repaired area with electrical tape. It's not as pretty as the paint job I removed but it protects it just fine and it makes it easy to remove the tape and show the repair if anyone asks about it. To paint it correctly to match the original finish is beyond my skills with paint. And I don't feel it's worth it to have the frame repainted by a professional.
As far as removing scratches from matte finishes, I think you'd want to reach out to or watch some RUclipss from the car repair or car restoration people. I couldn't find anything very helpful searching a bit. Most of what I found says that the problem is if you try to buff or polish it out you will turn your matte finish into a gloss finish. Which makes me think you need a product to touch up the scratch with the same type of matte finish you have now. Sorry I can't help any more but painting and finishing is its own art. If you find something that works please share what it is. Thanks again and good luck!
@@JimLangley1 thanks a lot. i reached DT swiss to see if they can give me a sugestion..no big deal thou..
@@Gledii I washed my bike yesterday after a really muddy ride and my carbon wheels have some pretty good scratches too now after thousands of great miles, so I know what you mean by no big deal 😊
@@JimLangley1 hehehe. yeah, i just read one good comment on a forum : "just embraced, a scare tells a story" :)
really useful to see each step! many thanks - I just found a small hole caused by a bottle mounted in the seat tube hitting the down tube - as the bike rattles down trails the base of the bottle was hitting the tube and eventually put a small puncture in it. I'll repair it and your video gives me the confidence to try! THANKS!
You’re very welcome Neil! Thanks for watching and please let me know how your repair goes.
Merci!
I very much appreciate this, Denis and it'll help my channel. Thank you so much.
what strikes me is how fragile such frames are. The properties of carbon fiber being stronger than metal are clear, however, in case of impact, Aluminum and iron would only dent. This repair seemed visually ok, im wondering if you measure the true strength on the tube if it will be strong enough only with these 2 layers of carbon fiber. thanks for sharing
Thanks for watching and commenting, appreciate it. Carbon actually is super strong but like all materials it has its weaknesses such as sharp objects and sufficient penetrating force. I don't have a way to measure the strength of the repaired tube other than riding the bike. I have ridden it a ton since the repair and it rides and performs as it did before the break. The way to look at the repair is not as just 2 layers of carbon fibers but all the layers that were in the frame already PLUS 2 more layers on top, so it should be even stronger than it was when new. Hope this helps explain more, thanks again!
@@JimLangley1 this make sense. im sure the tube around the crack is even stronger, i was just wondering exactly where the crack is. Ive seen dropbars delaminating and breaking like glass when pressure was added to a crack (under the tape). thanks for sharing
Nice idea. I found a repair kit at shopee. May i know what thickness of the carbon fiber should i use? Thanks.
Thanks for watching Roberto! The specs on the carbon provided are:
5.8oz - 3K, 2x2 Twill Carbon Fiber Fabric Weave, 6 in x 12 in
Predator doesn’t say how thick it is but I would estimate 3mm. You can buy the carbon from them. Hope this helps and thanks again!
Nice video! I was a little surprised how much the kit cost, though that's cheaper than getting it repaired by a professional. Repairs of the sort seen here are not 1K but more around 300-400$
Thanks for watching and commenting, glad you enjoyed the video! I'm also glad you live where things are repaired so affordably 😊
Great video, thanks for sharing. I have a Canyon Ultimate with a cracked top tube, quite substantial and covers about 60-70% of the circumference, localised to a single area luckily, do you think it is safe to use this kit to repair it? Thanks for your help in advance.
Thanks for watching and the question. It sounds like you have damage that's similar to what I had on my Cervelo, which makes me think the kit will work for you. You can also contact Predator and discuss your frame damage with them to see if they agree as they are the carbon experts. If you use it to repair your frame, please let me know how it works. Thanks again!
@@JimLangley1 Thanks for the prompt reply! I will definitely get in touch. I am also looking at using unidirectional carbon fibre and the hassle of layering it in different direction. I am still researching so could go either way...
Hi Jim, it doesn't look like preditor sell the kits anymore... do you know anyone else that sells them?
Thanks for watching and the question Chas. It looks like they changed the link. Here it is: predatorcycling.com/products/carbon-repair-kit Thanks again!
Is it possible to fix carbon rear drop out. The wheel is no longer able to stay in the drop out as they have worn down
Thanks for watching and the question, Chris. The dropouts on carbon frames are completely different than the tubes like what I fixed with the kit in this video. Dropouts are solid parts made with molds not hollow parts like carbon frame tubes. If dropouts wear out or break you need to replace them with a new dropout because if you try to glue another solid carbon piece to what's left of the dropout it'll break off.
So to fix that frame you should find a carbon bike frame repair company you can bring it or send it to because they'll have replacement dropouts and be able to properly install it in your frame to make it ride like new again. Here's one such company calfeedesign.com/carbon-repair/ Hope this helps.
How is the repair holding up Jim ? I can't see any comments on the final use of the bike. I was trying to figure out how long ago you did the repaired . Please advise, thanks.
Thanks a lot for watching and the question, Jo. I did the repair in August of 2022, so it's been 4 months of riding on it so far - about 1,000 miles on that bike with a lot of steep, long climbs here in the Santa Cruz Mountains. And it's been holding up just fine. I have not put anything over the patch yet which makes it easy to look at it and feel it to see if it's changing in any way and I haven't noticed any change at all. It's recommended to wrap it with electrical tape or paint it so as to keep the UV rays from affecting it and I'm going to do that soon. Right now all it's doing here is raining - we need it, too. Thanks again for watching and commenting. Hope this is helpful!
Thank you for your prompt reply .
Thanks for your advice, your reply and a great DIY video!
My pleasure David. Thanks a lot for watching & commenting 🙏 I’ll be interesting in hearing how your repair goes!
Good job Jim.😊
My pleasure Spencer, thanks a lot for watching and commenting!
I observed a crack in the seat tube of a Pinarello Prince SL (my dream bike at the time) soon after I bought it from a fellow who had at least 10 other Pinarellos hanging from the walls inside a room in his home. (Another room had as many Stratocasters.) (Guy obviously had more money than sense.) (On the other hand, who needs sense? He had a stunning 19-year-old girlfriend - he was probably in his 40s - and they were about to leave town to jet off to San Diego because they had heard the surf was up.) I asked him why he was selling and he said that he never rode this one. (I subsequently discovered the odometer showed he had put 10,000 miles on it. I suspect that this was his go-to ride until he cracked the frame somehow.) Word to the wise - buying a bike from a stranger for a price that seems too good to be true - check the frame over with a fine-tooth comb. Live and learn. Sorry, I digress. Being stubborn, I rode the bike for a year until a bike mechanic finally pulled me aside and told me I was flirting with catastrophic failure and likely certain death. (Tell the truth, I had been using this bike to crawl up and barrel down Red Mountain Pass in Colorado.) So I was left with the question of how to tell whether it was a superficial crack in the paint (what I had tried to tell myself it was) or a structural crack in the tube? I didn't try the coin tap (I actually tried it just now because I still have the frame - it didn't work - but I think my frame at this spot is aluminum, not carbon). So I thought I'd post what I came up with since it worked like a charm. Paint the outside of the crack with dish-soapy water, plug up all the holes in the frame, put the hose of a bike pump in a hole (plugging the space around it) and pump. Good news was, my idea worked. Bad news was, the crack blew bubbles like Spongebob Squarepants. (I promptly bought a Moots titanium frame with a lifetime guaranty, transferred over all the components, which were first class, and I'm still riding it 20 years later - all's well that ends well.) Anybody know how to fix a crack in an aluminum frame? Maybe a carbon patch like this would work.....
Wow, great story Citizen, thanks for telling it and for sharing the cool way you determined that your Pinarello was cracked and not just scratched/chipped - well done! As for how to fix an aluminum frame that should be a relatively easy fix for a bike framebuilder who works with aluminum. Here in Santa Cruz, California rocklobstercycles.com could probably do it for you.
Be interesting if the ride characteristics of the frame changed after stiffening it up in a flex section or if you could even notice. Masking tape doesn’t like excessive heat
Thanks for watching and the tip about not using masking tape to mask the frame off jonny, appreciate it. I do not feel any difference in stiffness but that's a subjective thing to feel and usually related to the size of the rider and their strength so another rider might. Thanks again!
Very helpful video, I enjoyed! Weirdly predator bikes has the kit removed from the shop and its unavailable on amazon. Wonder why that is...
Thanks a lot for watching Patty, glad you enjoyed the show, appreciate you commenting. I checked the Predator website and I still see the kit here: predatorcycling.com/products/carbon-repair-kit
@@JimLangley1 Oh now I see... obviously only available within the US. Got a "page not found" from Germany and with a few other countries I tried, choice for that is all the way at the bottom of the page.
@@Patty-qy8qh there are German carbon bike repair companies.. try reaching out to them and asking and I think they might offer something.
Awesome repair there Jim! That looks like a nice way to fix your carbon frame if you're able to use this.
Thanks for watching and commenting, Locks!
Hi, this is a great video. I have a similar crack on my bike. Bit less of a crack but more of a bruise if you like. I have been not riding for a while but want to get back on it and want to fix it before. This video gives me confidence that I can do it myself. Also I thought the coin was Australian $2 but reading the comments realized it is euro. Thank you the video.
Thanks a lot for watching, glad you enjoyed the video Purvag. It’s a pretty straightforward process and the folks at Predator that sell the patch kit are very helpful if you need any.
Your video is inspiring me to fix my carbon bike that’s been sitting in the closet for years. I hit a car head on, snapped my fork but didn’t notice the crack until I went to the bike shop. The crack I have starts from the top of head tube and goes down about a centimeter. Now I know you might be more of a novice to carbon repair, but you seem to have some good knowledge about bicycles. Would you have confidence in this kit for a small crack in a head tube? I think I’ve been told repairing carbon there is a bit more risky. Thanks!
Thanks a lot for watching and the question James. I'm glad my video has inspired you to try to fix your frame, but a crash with a car that breaks a fork is a major impact and it's impossible to know how badly your frame might have been damaged just by looking. That crack that you see might just be the tip of the iceberg so to speak.. with more damage inside the carbon that isn't visible to the eye. So, I would recommend you take the frame to a company that x-rays carbon frames to check for damage to the carbon. That way you can be certain that it's only that small crack and not structural issues in other parts of the head tube that could lead to a catastrophic failure later. I don't know where you're located but you can find carbon bicycle repair places in different parts of the USA that can do this and also in Europe. It shouldn't be too expensive to just have it inspected and you'll also learn how easily it'll be to repair the frame. I hope this helps and you can get back out on that bike. Good luck.
Is the carbon fiber patch overlapped when you wrap it around the tube or end it evenly. I would think that overlapping would give the repair the maximum strength.
Thanks for watching and the question- yes you can see in the video when I apply the patches that they overlap.
Yes I saw that the two patches overlap each other. My question is do the individual patches overlap themselves. When I wrap patch one around the frame does it overlap itself on the bottom? And when I wrap patch two around the frame (over patch one) does patch two overlap itself on the bottom. FYI, I have a cracked seat stay from the bike falling over sideways on a curb and I have ordered the Predator kit that you suggested. Thanks!!!
@@DaveIngels-x6d on my repair which was a top tube - pretty large diameter tube - the smaller patch did not need to overlap in my judgment but the larger patch that completely covered the smaller one did to join its ends and fully encircle the patch underneath and the whole tube. I basically followed the instructions in the kit.
For a stay, which is smaller diameter I think you might want to overlap the patch ends on both patches. I’m not 100% sure though. I think you should call Predator and ask to see how they would do it. I called them and they were very helpful. I had to call a couple times but I did get to speak to a tech guy when I got hold of them. Better to speak to an expert first before committing. Hope this helps and have fun fixing your frame.
Does this also work for downhill bikes?
Yes the kit is for cracked carbon frames whatever type you have Philip. Thanks for watching and commenting.
@@JimLangley1thx, cus I was wondering if it would work on frames that have to comprehend higher levels of stress
@@philipphd1158 you can also call the company and ask about fixing whatever cracked too.
Did you use a 50/50 epoxy/hardener mix. Looks great.
Thanks for watching, glad you enjoyed the video greaserleo. The kit I used provided the epoxy and hardener in a 2 to 1 ratio. The container of epoxy was 4 ounces and the hardener was 2 ounces and the directions have you mix them together fully. You can see the epoxy and hardener here: predatorcycling.com/products/epoxy-resin-and-hardener Hope this helps and thanks again!
I am thinking about purchasing an Trek FX Sport 5 all carbon right, however what is the tensile strength of the carbon?
Thanks for watching and the question vb. I have two Treks and both are great-riding bikes so I think you'll love your FX. It's actually made of Trek's OCLV carbon (Optimum Compaction Low Void). They've been refining and improving their OCLV carbon frames for decades now and there's a lot to know about it. You can learn more about it at this webpage on their site - they might give the tensile strength there www.trekbikes.com/us/en_US/inside_trek/oclv_carbon/ Hope this helps and let me know how you like the bike if you get it!
wow nice job!
@@faderblock thanks for watching and the great comment, appreciate it 🙏
@@JimLangley1 this is helpful video. will watch it again in future.
Does the heat gun go on hottest temperature. Thanks for your video and help by the way.
You're welcome Andy and thanks for watching. Heat guns differ in how much heat they put out and moving them closer or further away changes how intense the heat is too. What your goal is is to get the heat shrink tape to shrink. You can see in my video that at first the heat gun has no effect and the tape won't shrink. As the heat gun stays on a little longer it gets hotter and I move the hot air a little closer and at that point you can see that the shrinking starts because the resin/epoxy starts getting squeezed out in between the tape. So basically it's by trial and error how you figure out how hot it needs to be and how close you hold it. But you go little by little - a little more heat, a little closer until you see it shrink. Here again you could put a piece of tape on the workbench and heat it up as a test to learn what setting on your heat gun and how close to hold it to get the shrinking to happen. That would give you an idea what it's going to take on your frame repair. Hope this helps.
Great video Jim. Going to attemp to fix my MTB frame this weekend. I also see you like VW. I have a 2019 GTI. VW'S ROCK 👍
Happy to hear you found the video helpful Tom, thanks for watching and commenting. It’s not that difficult a repair, you can do it. Yeah my first car was a Bug and I’ve had VWs most of my life. Our Westy has been great. Never owned a GTI but drove my brother’s - super fun - just gotta watch for cops😊
i would do this for the top tube, which doesnt really carry much load.. but, would be more worried about diy fixing a seat or chain stay.
Thanks for watching and the comment, JogBird. It's basically the same process used by frame repair companies so it should work fine. Predator Cycling offers great support, too. You can discuss with them whatever you're trying to fix and they'll tell you if their kit will work for it.
@@JimLangley1 The only thing I wouldn't use it on is a fork since that is unsupported and very safety-critical if it does fail. Nice repair and I'd be very surprised if it doesn't hold up! Repainting tricky because of the pattern. Maybe have a look at the ETOE channel and respray the whole frame in an interesting colour scheme :)
@Ben C thanks for watching, Ben. I broke a carbon fork once and it wasn't fun at all 😊. Thanks for the tip about the ETOE channel, that guy has done some impressive paint jobs! At this point I'm still thinking I'm going to cover it up rather than repaint. But it's great to have such a helpful resource, thank you!
How long since the repair have you used your bike?
Thanks for watching and the question Andy. It's been over a year now and I haven't had any problems at all, the repair is holding up just fine. Thanks again!
I think you have made a splendid repair
Thanks very much, Gordon! Appreciate you watching and the great comment!
You made this look easy. After using this kit, idk how you managed to cut the patches so easily. The carbon fiber twill frayed so easily on me.
Thank you, Jim!
You’re very welcome Ricky, thanks for watching and commenting!
How long do you heat it for and if I don’t have a space heater what can I use? Does it just need to be near any hot air for 24 h to cure?
You could put it in a sunny small room that gets warm or turn the heat up in your house and put it in the smallest heated room near one of the heat vents but not on top of the heat vent. And you just wait until the resin has dried, turned hard. You can put some of the resin you mix on something and leave it to dry and check this to see when the repair should be dry. The resin will cure even if you don't keep it in a warm room but when it's warm the resin dries faster that's all.
My carbon is not uni directional so which way do I put my patches?
Thanks for the question. The patches only go on one way so they would go on just like I put them on in the video. I do that at 8:02. Hope this helps.
Honestly didn’t even knew this could be possible, so thanks for sharing!!! Only one comment, UV rays degrades/decay Carbon Finer some kind of paint would help a lot to preserving it
Thanks for watching and I'm happy you enjoyed learning it's possible to repair carbon bikes, dranenko. I think you missed the part where I talk about covering up the patch to protect it from UV rays. That's at 14:44
@@JimLangley1 super!!! And again amazing video, and really valuable information for the community!
@@alpl9605 thanks a lot, Al PL! I'm happy you enjoyed the video so much and really appreciate the kind words!
I'm going to give it a shot I'm kinda nervous
Thanks for watching and commenting, Robert. If you have any questions about your frame and the problem you're fixing you can reach out to Predator - the company that makes the kit and they'll walk you through it. And the kit comes with pretty easy to follow instructions. Hope this helps!
Hi, very nice repair vid! I have a crack around my front derailleur mount bracket - which was pop riveted and bonded in place, but had come loose. Crack is longitudinal, 2-3 inches long. Someone must have banged the derailleur into something. Will I need to wrap the repair material all 360 around the frame, or only over the crack + some side overlap?
Also, what is the thickness of the repair patches?
I'm glad you enjoyed the video Soren, thanks for watching and commenting! Your frame is cracked in a highly stressed area and that derailleur mount being pop riveted there complicates matters. I'm not sure you'll be able to fix this with a kit like the one I purchased from Predator (link to the company is in the description). I think to be safe you should take some photos of the damage and reach out to Predator or another carbon company to get their advice on whether you can fix it with a patch or if it needs a more extensive analysis (they can x-ray the frame) and sophisticated repair to deal with the frame and the front der. mount. Hope this helps and thanks again!
Very interesting. Seems like a solid repair, I hope it holds up and provides thousands more miles 👍🏼
Thanks for watching, Carlos! I'm sure it'll hold up - it's the same process basically that professional carbon repairers use - and I'm definitely looking forward to riding thousands of more miles🙂
Solid work ✌️
@@gianloplo thanks for watching and commenting, gianloplo, appreciate it!
How's the patch holding
@@tariusvadoom6489 thanks for watching and asking, tarius. The patch is holding up fine, no issues at all after hundreds of miles and thousands of feet of climbing the longest steepest climbs here.
Really cool video, the repair looks super strong. I watched some other videos where they put the carbon fiber on, and paint on top after instead of pre-painting. Any reason why you pre-applied epoxy?
Thanks for watching, Denis, the repair has been holding up great so it does seem super strong. The reason I applied the epoxy like that is just because that's the way the instructions in the kit said to do it and I wanted to follow their step by step to be sure to prepare and apply the epoxy, frame and patch according to their procedure. For the patches the epoxy goes on first so that you can flip them over and apply it to both sides of the patches. It definitely was a lot of epoxy and I probably could have used less and it would have been fine. Thanks for the great question!
Got mine fix for 300. By a professional. And they scanned the bike to see for other cracks. And painted it to match the old paint. It was black so pretty easy 😂 it was cracked all the way through though
Wow that's a great price, Benjamin, congratulations! Thanks for watching and commenting, appreciate it!
Thank you for the super didactic video
@@bronoueharaaaa my pleasure bronoueharaaaa - thanks for watching and commenting!
Great job Jim! I have a similar crack but it’s on the bottom stay of the rear triangle of a Specialized mountain bike - I’m wondering if a repair of this sort would be durable enough for a bike designed for a lot of aggressive riding
Glad you enjoyed the video Rossi, thank you for watching and commenting. Chainstays are usually pretty heavy duty so I think this repair would work well for your frame. The company that makes the kit is happy to look at photos and advise if the kit can fix the crack you have too. So you could ask them to take a look to make sure. Hope this helps and that you can fix it.
What temperature does the heat gun need to be?
I didn't use a certain temperature, I just made sure it was warm around the frame probably 75 degrees. You might want to watch the 2-part video that Predator Carbon made to show how to use their kit. Here's part 1: ruclips.net/video/tS7y6rZvBeo/видео.htmlsi=fRBF2NIn3wv3pZB_ And here's part 2: ruclips.net/video/0OZxeGNnSIU/видео.htmlsi=H8mlloaVuzsHao-1
Hi Jim, Is your repair still holding today?
Yes it’s still fine, thanks for watching and asking.
Used the same idea for repairing nordic ski poles. But this kit appears overpriced at $100, unless the carbon tape is of particularly good quality. I had a head-on collision on my trek Madone. The fork snapped, and I have replaced it. The bike rides "fine", but I am paranoid whether the frame also has cracks that I cannot see. I wonder if there is a way to reveal these small cracks (better than a coin). Don't wanna wrap each tube "just in case" :)
Thanks for watching and commenting, appreciate it. Yes, you can have your bike x-rayed to determine if the tubes were damaged in that head-on crash. Here's a website of a company not too far from me here in Northern California that does it for example: www.spydercomposites.com/ There's probably companies like this in other areas of the USA too. You could google "carbon bicycle repair" Hope this helps and thanks again!
Jim - great video - where can you purchase the non-adhesive compression tape?
Thanks a lot for watching Joseph, glad you enjoyed the video. I think you should reach out to Predator Cycling the company I bought the repair kit from. Maybe they sell the compression tape or know where you could buy it. If you find a source please let everybody know in a comment. Thanks!
Good job
Thanks for watching and commenting, appreciate it!
Great job Jim, I enjoyed your video..👍☘
Thanks a lot for watching HayBob! I'm happy you enjoyed the video and appreciate your comment!
What do you use to repair the carbon frame?
Thanks for watching and the question Ronnie. I use a carbon repair kit I purchased from Predator Carbon. There's a link to in the description and it's shown early in the video.
good work! Did you add the missing blue tape for the final touch? Looks good as new
Thanks, Zer0, appreciate it! I have been too busy to find the right color tape and everybody keeps wanting to see the patch 😀 so for now it’s still unfinished. But I will see if I can do a nice tape finish sometime soon I hope. Thanks again!
Good work Jim! As usual, you are crafty and meticulous.
Thanks very much, Denis! I'm happy you enjoyed this video and appreciate you watching and the great comment!
Wow great job Jim, looks amazing we'll done & thanks for sharing.
Thanks a lot, Graham! I'm happy you enjoyed the repair, it was a fun one!
Hi, how did it hold up after 1 year?
Thanks for watching and asking vadim, appreciate it. The bike is fine, the patch has held up perfectly. Thanks again.
@@JimLangley1 I had the same question, but thought I'd scrub the comments first. Glad to hear it has held up!
@@jacksobe thanks for checking out the comments to find the answer jacksobe, appreciate it! I did two climbing rides on that bike last week and it's working great.
Can we get an update on the frame
Still fine, no issues. Thanks for asking!
Awesome video, how is the frame holding up? My bike shop just found a crack on my seat tube, I'd love to save $ doing it myself, but I'm not sure it'd be safe/sustainable since the tube holds so much more weight. Any thoughts?
Thanks for watching, Paige, glad you liked the video! My repair is holding up just fine. I haven't had any issues at all and I've ridden the bike a ton.
For your issue, the very first thing I'd do is to find out if your frame is covered by a warranty - most frames are. I would think the shop would have thought of that straight away but in case they didn't that's the first and best way to deal with it because the company that made the frame knows the most about their frame material, design, etc. and if it broke they might replace it under warranty. I know people who are on the second even third frame this way.
If that's not an option, you might at least learn from the company whether the damage is repairable. If you want to do it yourself, take a photo of your frame crack and reach out to the company that sells the repair kit I used predatorcycling.com/products/carbon-repair-kit They'll look at your photo and tell you if the kit can fix the crack you have. Hope one of these options works and you can save that frame or get one under warranty.
@@JimLangley1 thank you so much, I'm going to reach out to the original owner to find out about the warranty!
@@paigesettar2543 good luck!
One year later now, did it hold up ?
@@krisschmitt4146 thanks for watching and the question Kris. Yes it’s holding up fine. Looks the same and the bike rides the same too. Thanks again.
wow ! awesome !
Thanks a lot for watching and commenting, glad you enjoyed the video so much!
Are you based in the USA? How come you use the 50 cent Euro-coin to tap on the crack? That caught me offguard. Otherwise very informative video!
Hey thanks for watching and the great question Ikarim - I wondered if anyone would spot the coin I used. I used it only because it looked better on camera and it’s thicker than a quarter- and yes I’m in California. Thanks again for watching, glad you enjoyed the video!
Nice video thank you.🚵♂️👍
You’re very welcome, William. Thanks for watching & commenting, glad you enjoyed the video.
Thanks Jim - that was very informative.
You’re very welcome! Thank you for watching, glad you enjoyed it!
Nice thing about a well-made steel-framed bike is…they almost _never_ break. Just like well-made samurai swords. Funny how that works…🤔😉😺
Thanks for watching and making this point Stephen. A steel frame subjected to what happened to my carbon frame would just get dented, it wouldn't crack. You could keep riding both frames. The dent in the steel frame wouldn't be likely to change. It would look ugly but the tube probably wouldn't ever crack or fail. The crack in my carbon frame would probably have grown larger over time and might have continued all the way around the tube causing it to break.
@@JimLangley1 Agreed. Personally, I'm still of the view that steel is an excellent material for bicycle frames. It's strong, tough, and resilient. Cheers.
Don't use wet n dry to remove paint it takes ages use a Stanley blade at 90 degrees and plane paint of it takes only minutes 👍👽
Removing paint with a razor blade is fine with steel frames since the blade can’t cut into steel. But it can cut carbon. That’s why you use sandpaper. Yes, it’s slow but it lets you remove the paint carefully and not risk damaging your frame any more than it already is.
@Jim Langley mate the blade doesn't touch the carbon it slides once you reach the carbon layer and you can see no more white ish lacquer flakes coming off,I've been professionally repairing frames since 2009 and come fram a composites back ground, at the peek I was doing 10 frames a day and you need at that point to find fastest way to achieve your goal
@@guinnesslover2970 appreciate you sharing your expertise and tips. My concern is that this kit is for beginners and comes with and says to use the included wet sandpaper. Also cracked carbon frames and rims, etc can cut you if you’re not careful. I wouldn’t want someone sliding a blade across a tube to run into the crack and splintered carbon. But I believe an expert like you can do it and I am sure it’d be a lot faster. Thanks again.
You only needed10ml of resin fo the whole job ! Max you need is same weight of resin to cloth
Thanks for watching and the tip guinnesslover. When trying to get the ratio of epoxy to hardener right you can end up with more than you need. The compression (shrink) tape and heat squeezes out the excess resin.
Well done! Lucky it broke in a less critical and linear area. The shrink tape was an easier way than vaccum bagging. Steel is still real though!
Thanks a lot, David, appreciate you watching and commenting! Yes, it was lucky the break was there and their shrink tape was truly ingenious and pretty easy to use, too. I love my steel bikes, too😊 Thanks again!
Nice 50 cent coin ;)
Respectfully, I don’t think that frame can be fixed. I feel like that’s a catastrophic failure waiting to happen with a bandage on it . For me, the only way to fix a carbon fiber frame is to have a good steel frame.
Frames are built with ~4 to 8 layers of carbon depending on where the strength is needed. DO NOT patch your bikes like this. There's a reason why it costs so much to patch a frame. They put more than 20 minutes and 2 bandaids into the repair.
Thanks for your opinion bentBuilder but this repair took hours and the frame now has its original layers plus 2 more. It’s a kit designed and made by a carbon frame company and they confirmed it was correct for my frame damage. I have many many hard miles on the frame now and it’s fine. Carbon is much stronger than it might seem.
Don't repaint it, a gentleman in my club has the same kind of repair and he's left it as is. All he did is spray it with clear coat. Cheers!
Thanks a lot for watching and letting me know your clubmate simply clear coated his similar repair, Valiant. I appreciate it!
Imagine trusting your life to a company that has “predator” in its name.
🤣
Please wear a proper face mask when sanding carbon!
Thanks for the safety tip, appreciate it!
Hello Jim.
I hope you are aware that this is a replacement repair that does not guarantee the transfer of loads like the original. After such a repair, there are many dangers, which the strength of the materials speaks of. I will just mention that the cross-section of the same piece is different than that of the base element, there is still a notch there and there is a large material fault, which may cause bending stresses. In addition, there is a high randomness of execution, no tests and no control after repair beyond the control of the coin :). Generally it is very risky what you did, but .... whereas you are a sensible person with experience as a bicycle mechanic, you have all the risks at the back of your head.
I recommend not to paint this bypass and make a visual inspection after each ride to see if there is a crack. On the other hand, the rupture of such a thin patch will be very violent and rather total.
Apart from the topic, I am a little surprised people buy a product as risky, poorly made, dangerous and easy to damage as carbon bicycle components. In my case, I only have a carbon water bottle cage, which may also do some harm in the event of a breakage.
Best regards and good luck with this frame.
Thanks for watching and for your thoughtful reply Michal. I appreciate your concern for my safety. I probably should have explained more about the patching in the video. I'll do it here to try to address and ease your concerns. I bought the patch kit from Predator Cycling, a company that manufactures carbon frames and I first discussed my repair with them and showed them photos of my frame's crack. They told me that their kit was made for these types of repairs.
The way the repair works, the carbon patches saturated with epoxy are pressed hard onto the sanded and cleaned carbon of the frame with the heat shrink tubing. During the process of drying, the carbon patches and carbon frame become one. The carbon patch presses down into any groove remaining where I sanded the crack. So, if it all worked as designed, that area of the frame is now 2 more layers of carbon thick and the crack - at least on the outside of the frame should be completely filled and reinforced, too. Thanks again!
I've got to disagree, there are no dangers the more overlay of carbon the stronger it becomes, I've repaired lots of mtbs in a similar manner, even chain stays and they are bullet proof, there's no way that would continue cracking or break, its alright saying this will happen and that will happen when you've never experienced doing a carbon repair, or not really knowledgeable about it, it's no different from welding a hole up in a piece of steel, it's just a bike it's not under serious load, people like you worry about the smallest things 😉 that frame will be solid
@@shaunsmith3660 Thanks for the comment, but I definitely disagree with you. The fact that you have repaired a hundred frames and they are still alive does not mean anything. If you had any knowledge on this subject, you should know what the fatigue calculations look like. I am referring to the material strength course, especially please pay attention to the section devoted to fatigue analysis.
@@mutos82 I can see you you are ignorant and clearly never done a carbon repair in your life, you stick to your figures and calculations on that piece of paper or screen and let the big boys fix stuff 😉
@@shaunsmith3660 thanks a lot for sharing your experience fixing carbon bikes, Shaun, appreciate it a lot!!
😮
This is not a proper job to repair any crack.
Thanks for watching. Please explain why you think that.
It is not as good as prepreg + autoclave/rtm (as it is made at the bike manufacturer) due to small compression, not optimal epoxy to carbon ratio (more epoxy = more fragile) and possibly there could be air bubbles/voids in the laminate (not this case as it seems, but usually it comes with diy aproach)
@@Anton-zb9dc thanks, Anton. This is a kit that comes from a maker of carbon bicycles, so you're getting what they designed to fix cracks, i.e. what a professional carbon manufacturer recommends and that includes the carbon fabric, the epoxy and hardener in exact measurements and how to mix it (no bubbles) and how to compress it - in a different way than a mold is used but still very effective. But I can see how if you didn't use a kit and tried to figure out how to buy the materials and do it yourself you might not end up with a proper repair. But with this kit, you'd have to not follow the directions or make a major mistake.
It would be cool if you would inspect the repair from inside with endoscope to see if there are any drips of epoxy or something similar. That would be interesting!
@@Anton-zb9dc yes, that would be cool. I don't have an endoscope to do it, though. But it's a good idea for sure. Thanks!
unlucky you did nt get the pleasure of breaking it ,the wind done the damage damm ,they re expensive fad,, carbon bikes ,,,chromoly all the way
Thanks for watching and commenting, theresnobody! Actually I've "had the pleasure" of breaking multiple frames and it can be a lot more pain than pleasure when you hit the deck, ha, ha 😆
I've just cracked my steal seat tube