Seeking A Perfectly Round Bike Wheel!
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- Опубликовано: 23 мар 2024
- Getting bike wheels perfectly round just takes a little time and patience. Watch me make a good wheel a great wheel in 9 minutes. #bikerepair
Be sure to watch my full video on building this radially spoked front wheel:
• How To Build Radial Sp... 
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Roundness is always more important than horizontal movement. But the king is that all the spokes must be the same tension !
I must send you my book as soon as I finish up .
Please don't take this comment as criticism, rather a suggestion. It would have been helpful if you panned out slightly so we could see your spoke tension adjustments to understand the approach i.e. which spoke on what side in relation to the high/low spots.
That's a totally valid criticism so no problem Kid... please allow me to explain that I was hoping/assuming viewers would read the description and see that I provide a link to the full video of this wheel build. But, I completely understand how most people just watch videos and don't dig any deeper. In any case to see what's missing in this video, please watch the full show: ruclips.net/video/OLtvQoSMm60/видео.html Note that you don't actually need to watch the full video. I put timecodes in all my long videos so you can use the scrollbar or timecodes in the description to jump to just the parts of the video that you want to watch. Also, I have an even longer video on wheel building that goes into even greater detail here: ruclips.net/video/XUqul03hbZ8/видео.html
In case you don't want to watch those videos. To remove high spots you tighten spokes and always in pairs. So you would tighten a left and right spoke. If the hop was longer you would tighten, left/right, left/right, left/right for example. And to remove low spots you do that same but you loosen. You always turn spoke nipples a small amount at a time too, usually about a quarter or half turn. Then you spin the wheel, check how you're doing and make another adjustment. Oh.. the reason you turn pairs (left and rights) is because if you turn a spoke on only one side of the rim you will take the wheel out of true laterally. The goal when removing high and low spots is fixing roundess issues while keeping the wheel true laterally. Okay? Sorry for any confusion in this video and I hope this helps.
Thanks for the video Jim, I recently did a wheel build and took your tip of looking at the rim and stand side on when truing for roundness and it really helped.
I’ve also noticed that the more rims I build, the more I can feel which spokes need tightening or loosening to get the rim true and round (sometimes some odd spokes are very tight or very loose).
I’m also starting to rely more on feel and sound as the rim gets closer to true because it’s much easier than seeing what is happening.
I took video footage of me building up a rim following your video and will upload it to RUclips when I get it trimmed down (currently it’s at 1 hour of footage!). Really want to see your channel promoted more because it’s a wealth of information and you do a great job of showing a more than one option to solve many key steps.
Thanks for watching and another great comment indoor! I'm so happy to hear my vids are helping you with your wheel building and really appreciate you supporting the channel!
That's not an ugly rim seam. Usually that process works a charm, and I have the patience for it. What pursuit of perfection may bring is large differences in spoke tension. Deep section rims with low spoke counts, you pass the point of diminishing returns quickly.
Thanks for watching and commenting David. The goal is to end up with a nice true wheel and balanced spoke tension within whatever range it's supposed to be (usually spec'd by the rim maker on newer rims). So long as you don't get a bad rim - and there are bad rims and defective rims as you know - you can usually do a decent job with whatever you have. But, it can take quite a bit of time with some modern deep profile carbon rims with aero spokes and hidden nipples and so on - they don't make it easy for wheel builders 😊
Hi Jim, here's a fun question for you...
Let's say that a rim was not manufactured perfectly round (extrusion/bend/weld) barely within industry accepted limits, so those hops are necessarily compensated for via spoke radial tension variations. You mentioned at the beginning that you'd never feel those hops when riding, so how do you personally trade off radial trueness vs. spoke tension uniformity?
There are those who argue that tension uniformity is primary for reasons of wheel durability/safety, and that putting too much emphasis on radial trueness may be a "dangerous mindset". SpokeCalc and Parktool's Wheel Tension App seem to put a lot of focus on tension uniformity with those radar plots, variance calculations, etc., so I was just wondering where you sit on this topic ;-)
Thanks!
Thanks Chuck, that is a fun question. In my opinion, the answer is that how true and round the wheel is wins out over how equally tensioned the spokes are. If you focus on perfectly even tension or close to it, you will rarely if ever have a wheel that looks the way the vast majority of cyclists expect a wheel to look i.e. very true and round. There are many reasons for this such as variances in spoke dimensions and like you pointed out, issues with rims too.
But, you do always want to try to get the "worst" spokes (ones not up to the tension of the rest of the spokes) up to par so that you don't have any spokes coming loose. So you do try to balance the tension as best you can while still building a wheel that passes the eyeball test that consumers, bike shops etc. use to QC the wheel and make sure it's true and round enough. Partly it's also because wheel builders can't stand visible imperfections in wheels they build (I've worked with quite a few). That accounts for the popularity of truing stands with dial indicators on them that allow truing and rounding way past what you can see. (I've tried several of these and always go back to my Park stands without.)
But you can do that and still ensure that the spokes, while probably not perfectly even tension will all be in a reliable tension range and thus know that you built a very nice wheel. You mentioning Park Tool reminded me that I attended a wheel building class put on by my friend Calvin Jones of Park Tool - it was in the late 1980s. He came out here to CA to do it. The class opened and Calvin clicked on a slide projector and on the screen was a Ferris wheel and Calvin talked about how the first Ferris wheel was constructed just like a bike wheel. It was a great class. If you ever get a chance to meet Calvin don't miss it.
So when you are building a new wheel and spokes are loose, you eliminate the high spots by loosening the other spokes. On a finished wheel like this, you tighten the spokes on the high spot area to correct it.
Hi ender, what you wrote is correct. To explain a bit, you always have a choice whether to loosen or tighten spokes to remove high and low spots and get wheels round. When a wheel is just laced and you're starting out truing it, at that point you don't want to add any unnecessary tension to any of the spokes because that can cause problems. So it's best to get the wheel as round and true as you can mainly by loosening spokes. Now when the wheel is almost finished and fully tensioned you finish by getting it as round and true as you can. Often at this point there are very minor high and low spots. Again you can choose to loosen to remove the low spots or tighten to remove the high spots. But, since the high spots are easier to see and especially hear, it's easiest to fix them. Also, since you are finishing the wheel, this extra tightening which is very minor (usually only half turns), helps to add a touch more tension to the whole wheel. And this helps tighten the wheel and balance the tension. Hope this helps.
Thank you. This is very important tip and I think many people missing out that point.
@@ender4903 you’re very welcome!
👍👍Great! Jim
Thanks a lot Jon! Appreciate you watching!
The truing stand helps a lot. i had to improvise with a piece of painters tape on the frame as guidence. it got as good as it gets :P. Jim, if i have a couple os pokes in one side that are quite loose, however the wheel is quite true. if i add some "minimum" tension to that spokes and release the other side accordingly, i can keep the laterla truing but the radial is screwed...Is this a "common" issue? or is an indication that the rim isnt good? thanks
Yes a truing stand does make it easier to see. In case you didn’t see my short vid - Performance Bike dot com sells their Spin Doctor stand for $60, amazing for that price. Now on your wheel, you might have an issue with that rim. But there’s another way to add tension to loose spoke without touching those loose spokes. To do it you tighten all the other spokes and those loose ones will get tighter as a result without tightening them or loosening the one across from them. And the wheel should stay true and only at the loose spokes should the rim get a little higher. So think about that approach while inspecting your wheel - it might solve your issue.
Jim: isn’t the balance of spoke tension for all the spokes around the entire wheel impacted? What is the greater good?
Thanks for watching and the great question rivnuts. What you want is both balanced tension and a wheel so round and true that no one will see anything wrong with it when they spin it. So once it's round and true as you want it, you then check spoke tension and if any spokes are not within the range spec'd for that rim then you would increase the tension of all the spokes slightly to get that one spoke a little tighter and make it up to what it needs to be. That's the way most pro wheelbuilders achieve both "perfect" wheels and balanced tension. With variances in rim and spoke construction, tensions spoke to spoke usually are close but not the same, so you have to work with what you're given and that's how you make it work. Hope this explains and thanks again.
Hi Jim. When you're truing a fairly deep profile carbon rim. 55mm . Therefore a pretty rigid rim. Are you moving the rim or moving the hub relative to the rim. I would think the latter. But id like your opinion. Thanks.
Thanks for watching and asking a really interesting question Paul, kind of a head-scratcher. I had to think about it a while to explain my take on it, which is that it's the rim that moves. I believe this is what's happening because you can see rims move as you make adjustments with the spokes. You can see it with the aluminum rim in this video. And I've trued giant 90mm carbon rims and they move too. Also, I think if the hub was actually being moved as the spoke was tightened and essentially shortened, then I think the hub would change position in the truing stand and you would need to keep pushing the hub back fully into the uprights. Some truing stands won't let the hub change position too. Hopefully some engineers will see your question and chime in with a more scientific response which would be interesting to see. Thanks Paul!
Hi Paul and Jim,
I’m a chemist (retired) but I did pretty well in basic physics and this question fits comfortably in the basic category. There are two ways a wheel can be out of radial true. 1. It can be non-circular, i.e. oval or some lumpy shape. 2. It can be circular, but not coaxial, i.e. the center of the rim does not coincide with the center of the axle. These are not mutually exclusive. A wheel can have both types and, particularly with a new build, probably does.
For the case of non-circular aberration, it’s not too useful to think of the axle moving. In fact there may be no net movement of the rim and axle when truing a non-circular error depending on the details of the shape.
For a non-coaxial aberration, we get to use one of a physicist’s favorite words. It’s relative! You can think either of the rim moving with respect to the axle or the axle moving with respect to the rim. Makes no difference.
@@markholm7050 thanks so much for considering the question, putting on your physics cap and providing a scientific answer Mark, I appreciate it. I think I even understand it 😊
Top video, Jim.
Reminds me of the old saying...
"Patience is a virtue, but there comes a moment when you must stop being patient and take the day by the throat and shake it. If it fights back; fine. I'd rather end up bloody at the end of the day, then unhurt with no progress made, no knowledge gained."
@@JimLangley1 I’m glad I contributed something helpful, even if it’s only a small thing. Pretty much the same analysis applies to lateral truing, except in lateral truing we are concerned with the angle between the axis of the rim and the axle.
Dish is a different matter. We don’t usually think of dish as varying around the rim. That would be the same as being out of lateral true and we think of and deal with it as lateral true. So dish only has one type of error, the type that can be equally well be thought of as moving the rim or moving the axle.
Jim. Nice session. Was all of the minute hop a result more to do with the radial build pattern?
Thanks
Thanks for watching and the question Richard. In my other video that this one is taken from where I build the radial wheel, I explain that truing and rounding is the same process for cross-spoke and radial wheels. And, you get these same tiny hops in both wheels, radial and crossed-spoke. You want to start truing and rounding the wheel when it's a low tension and at that point you do your best to get the wheel as perfectly true and round as you can get it. That way it tends to want to stay round and true as you add spoke tension and finish the wheel. But, you often end up at the end having to make small small adjustments like this to get the wheel as perfect as you want it. It's not the result of the spoke pattern, more a result of the rim. Hope this helps and thanks again!
@JimLangley1 that's a great answer. Thank you Jim.
Bill Mould has taught me to remember that throughout the wheel build. If I ever get back to California, I'd like to pay you a visit.
@@richardcoppedgejr6871 Thanks for mentioning Bill, Richard. He's a fantastic resource to wheel builders everywhere. Here's a link to his vids for anyone interested www.youtube.com/@BillMouldWheels
Here’s a question, Jim. I have a Reynolds carbon 29er XC rim with DT Swiss 1.6mm steel spokes. Some spokes got loose and when “fixing” it I snapped a spoke. The wheel is now totally warped and a right mess due to my efforts to repair it. I have no data sheet on the correct tension. It’s a rear wheel - asymmetric. So, is there a way of starting from scratch to fix this wheel. It also looks like the spokes are losing tension a few minutes after I tighten them according to my Park Tool tension gauge! How do I go back to basics? Thanks, Laurence
Thanks for watching and the question Laurence. Yes, you should be able to fix that wheel. The first thing would be to replace the broken spoke. That spoke is on one side or the other of the wheel. To start to fix the wheel you want to get that replaced spoke back close to the tension it was before. To do that you pluck a spoke on the same side of the wheel as the spoke that you replaced and then you pluck the replacement spoke. Listen to the music. Keep tightening the replacement spoke until it makes the same sound as the one already in the wheel.
Now, since there are some other spokes losing tension you would continue your listening to same-side spokes as you pluck one at a time. Some will have a high pitch. Those are the ones that haven't changed - are at the same tension or close to it as before the spoke broke. The spokes that aren't as high pitch when plucked are the ones that need tightening. Using this basic process you should be able to even out the tension. And, as you do this the wheel should become more true and round.
Please understand that working with spoke tensioning is a gentle slow process. Usually you only turn the nipples 1/2 turn tighter on the looser spokes and then pluck and listen. Easy does it. Don't crank any nipple a bunch of turns at one time. Go easy. 1/2 turn at a time, check progress, go another 1/2 turn and so on. You are gently bringing the wheel back into tension balance. It's actually really fun. Don't rush. Learn from experimentation. Don't get frustrated if it takes a while for the wheel to start getting better. That's normal. If it frustrates you, walk away and come back later when you can focus and relax and enjoy the process.
Give this a try and let me know how it goes. I'm happy to offer more tips but this is a good starting point and if you get good at this technique it will help you in truing and rounding the wheel. As you balance the spoke tension this way the wheel should stabilize and stop losing tension. Have fun with it. Let me know how it goes. In case it would help I have another video where I fix a guy's crashed carbon wheel - it's a road wheel but the process is similar to what I'm telling you to do. Here's a link: ruclips.net/video/NyPGQrNfUFU/видео.html
@@JimLangley1 thanks, Jim, that’s an excellent and comprehensive reply, however I’d say all the spokes are completely “out of tune” due to my fiddling that’s why I’m having to start from scratch and “yes” I was certainly over-rotating the spoke nuts. I’m not patient. I can see now this is a delicate process. I therefore have no reference point for what the correct tensions should be. Laurence
@@lanceblack888 that's fine too Laurence. In that situation a good way to work is to get the wheel true side to side and round but by only loosening spokes. Don't tighten any. Just gradually loosen while you get the wheel true and round and keep working until the wheel is nice and true and round too. Because you're only loosening spokes, you're taking any "bad" tension out of the wheel and when the wheel becomes round and true again you'll have it back to where it was before the spoke broke - except it now has almost zero tension in the spokes. What you've done is allowed the rim to relax back to its normal straight round shape since no spokes are pulling it out of true or out of round.
Once you have the wheel round and true you want to check it for centering with a dishing gauge or by flipping it around in the truing stand. If the rim is not centered (dished), you'll want to adjust it so that it is. And when the rim is centered and the wheel is round and true, you can then very gradually bring the wheel back to full tension. You do this by going around the wheel tightening the spokes 1/2 turn at a time. Always check after each time around the wheel that the rim stays centered and that the wheel stays true and round. You'll have to go around the wheel maybe 6 times (maybe a little less or more) to fully tension the wheel.
Keep checking the tension with your meter. Shoot for 120 kgf on the right side spokes. Don't worry about the left side spokes as they'll end up wherever they need to be to allow the rights to be at 120. That final tension should result in a wheel built similar to how it was when you got it. In my recent video on building radially spoked wheels, at 33:15 I show the tensioning process in some detail. Okay? I hope this helps.
@@JimLangley1 this is a brilliant explanation, Jim. A thousand thanks 🙏 Now, one last question. My Park tension gauge doesn’t show kgf. It shows numbers from 0 to 45. What are these numbers. They can’t be kgf. How does this equate to kgf? I do have a Park chart, but it’s confusing. My spokes are 1.6mm. Best wishes, Laurence (the Park tool reading seems to vary for the same spoke after a few minutes - maybe these spokes are relaxing or losing tension immediately?)
@@JimLangley1 another pertinent question (I hope). I can’t find the exact width replacement spoke. I can find the same end width (so they’ll fit in the spoke holes) but the body is 1.8mm and not 1.6mm. Will it make any difference if a spoke is 0.2mm wider than the rest? (And what’s the bit called that holds the spoke into the rim? A spoke bolt? Spoke nut?) Laurence