Hi my rear derailer is sitting to low when on smallest cog i adjusted the b screw all the way in but its still sitting to low and the chain is rubbing on the derailer please help.
I don't understand why some of the other rear derailleur videos fail to mention this. I actually had to search for this specifically to find this excellent video.
I still can't find info on my 1970's Suntour version as the cog is always 2 inches from my cog! This is clearly one VERY misunderstood screw within the cycling world
Just finished my first complete rebuild -an 80's Stumpy--total strip down,new bearings everywhere,etc--It's working very well and looks great too..Got it from a dumpster and now it's like a new bike..Your videos were extremely helpful...thanks very much and all the beat.
2:14 ah, I finally got it now, the space needs to be so the small deraileur cog moves individually from the bike's cogs without forcing one another into position. When they are too close the chain kind of forces one another into a fixed position.
Hell yeah! After months of cracking my head I finally got it! Got my Sram NX 1x11 drivetrain shifting like never before. Thanks a lot buddy! This was the fine tuning that I was looking for.
This was very helpful. I bought a used bike that had the cog to close and the shifting was of in the lower gears because of that. I folowed your instruction and helped. Then I adjusted the cable tension got perfecly crisp shifting. Thanks!
Your videos are the go to source for me if I run into an issue I can't fix. Must have watched a hundred by now. Always informative, quick and clear, thank you so much RJ!
Nice one, I had mine set too far back after swapping frames and was getting erratic shifting and slipping in smaller gears. followed this and super crisp shifts again.
RJ The Bike Guy is my "go to" place to visit if I want to figure out how to set up or adjust something on a cycle. Absolutely brilliant videos - thanks RJ!
thx I discovered this makes big difference to shifting speed and accuracy- on my ultegra 8000 it was set way too far back and I was about to replace it - now sorted 👍
Wait a minute. I’m going to give this a shot. I just replaced my 11-34 to 12-42 today, but it was rubbing so i thought about getting a goat link which will take a few days upon ordering or local bike shops were close because it was late saturday now, since i found this video, i might give this a shot and hoping to test my bike at the trails after, thanks.
Thanks; I'd always wondered about that! Just changed from an 11-27 to something-32 tooth cluster, and new 105 GS cluster. Am now trying to tweak the adjustments. Your vids are a great help!
On a road bike rj you can get this thing dialed in great and make that shift crisp as heck man. I always adjust them at my shop for people and they all com back saying wow the shifting is so much better. When they are correct it's a big difference.
I'm reasonably good at adjusting my rear derailer but on my last tour no matter how I fiddled with it it would jump from 8 to 7 (9 speed derailer) when under heavy load e.g. on hills.I'd have to go all the way to 9 to stop this jumping. I couldn't reproduce the problem on bike stand or at the side of the road and with a light load it was just fine. In desperation I took it into a bike shop in Rolla MO. They were originally as mystified as me but after taking it out for two test rides they managed to figure it was the B screw adjustment. Adjusting the B screw so the jockey wheel so it was as close in as possible fixed the problem.
Peter Jack It seems when you adjust gears on a stand it is fine for gear speed but not for representing chain tention or load. Does chain tention relate to gear adjustment, should tention be done first.
Trek520 rider Most of the time 90% gear jumping is related to bad indexing after setting up the Low and High limit screws. The derailleur cable must have some tension when on the smallest cog. The indexing for the inner cogs is done through the Derailleur cable tension adjuster. What they told you is ridiculous and a complete lie. The only reason why you need to set the B screw is to stop the guide pulley from getting too close to the cogs causing noise and grinding issues with the chain.
It may be, as you say, the least important screw on the rear derailleur, but if it's way out of whack (like it was on mine), it can make a huge difference when you're on the large cog. Thanks!
I learned this the hard way my rd cage was too slack because i didnt mind the b limit screw at all and the rd cage snapped while in a race and gotten last place but thank you for the tutorial this really helps
Request: a video describing in detail when it's time to change either of your casette, chain or chain rings - including tools used, etc. Thanks, and keep up the good work.
The chain, cassette and predominately used chainring (e.g. the middle ring on a 3 x setup) generally wear at the same rate on multi speed setups. 1 x drivetrain is a bit more of an exception because the narrow wide chainring teeth are usually taller and so you can usually get away with replacing just the chain and cassette. You can usually tell if your chain and cassette (and possibly chainring(s)) are worn out because the chain will skip over the cassette under load, i.e. riding up a hill. It used to be a myth that pressure washing your chain, cassette and chainring(s) somehow forced dirt into the system, thus wearing it out faster. That couldn’t be further from the truth! If you apply lube to your chain before pressure washing everything (be careful not to blast water into your wheel or bottom bracket bearings), dry the chain with a rag and re-oil it, you will vastly prolong your drivetrain’s life.
Struggling a bit with my Shimano 11-speed XT rear derailleur. You state that the b-screw is not critical, yet I seem to have constant issues with the pulley rubbing the low cog, which is a 46 tooth pie plate! The b screw seems very critical to these setups given the gap between the low and the second cog.
What do you do when the screw is all the way in but its still hitting ? Is it a weak spring that is in the housing that bolts onto the frame ? Will you make a video on how to chance that spring ?
I bought the Garbaruk 11spd cassette for my 1x11 GRX rear der. I adjusted my B screw to handle the Garbaruk 46t cog from the Shimano 42t that I replaced. However I don’t feel like the Garbaruk shifts as smoothly as the Shimano HG cassette was. Now I kinda regret it and should have just got an XT cassette instead with the 46t cog
@@RJTheBikeGuy it turned out to be the gear cable that sets in the derailer. It was allowing it to push out instead of holding its place and the gears wouldn’t change. This video just kinda led to it and helped haha thanks!
Hi Jim here, Great video. I have an old bridgestone mb2 equipped with a 13X 34 7 spd cassette and a shimano xt long cage rear derailler. The upper guide will always hit 34t gear even when b screw fully screwed in. Even installed a longer b screw where it still upper guide will hit 34t gear when fully screwed in. Is the pivot spring worn out? Do I clean derailler pivot bolt by disassembling. I have 15 other bikes using the 13x34 7 spd set up where most all work perfectly. Any ideas 💡? Thanks, Jim-
Small tip: While you are turning the screw, you pull the RD slightly away so that the B tension screw isn’t pressing firmly onto the B link or the RD hangar. And you check periodically whether or not you got the correct spacing. (Now if your bike is new or your RD is new, Shimano and SRAM gives you an indicator, so finding the correct spacing is a lot easier for rookies, you no longer need to eyeball or use a ruler.) The reason being is that the tip of the screw is very hard, and is often rough. So that it can very easily grind a divot into your hangar or B link, especially when you are doing that first time, and you are turning the screw back and forth.
Just got a new hyper eride mountain ebike with Falcon derailer , dont know knothing lol. Is this screw also the way to tighten the chain ? or is the only way to tighten the chain remover links? Thanks
I was hearing a crunching sound when I went up a hill in my lowest gear, or biggest cassette ring of 34. Adjusting the B screw solves the issue I think. The pulley was too close to chain ring. It's the least critical adjustment, but it t can solve some unpleasant noises.
My B screw doesn't seem to do anything when adjusted. I have a Shimano tourney set up and it's got this very tall 1st gear and the cogs are slapping against each other, I'm getting that exact grinding shown here because they are too close together.
Have a Shimano Tourney Drailler and it is to close to the first gear, and the screw is all the way in. Is there a fix for this. or will I have to replace the derailler and what would be a good one to go to, as this none is not very old and was not used a lot.
HELP! My shimano SIS lacks the B-screw and the pulley makes contact with the larger gear of the cassette. Peple are suggesting to adjust the housing lenght to avoid that. Does it really work? And how to measure it? Thanks!!!
This is a description of how to shift up the best. You should also consider having the cage far enough away from the cassette when in the 2nd to largest cog to clear the largest cog when shifting down.
It's not clear which way turning the screw CW or CCW makes the adjustment. when he was "backing off" was he actually screwing in or screwing out the b-screw. It's not clear from the video.
HI. I have a suntour derailleur model EDGE 4050, I dont know if is missing a little plastic cube, . It seems this derailleur doesnt have a B screw or something . In the moment I mount chain... there is nothing that stop it, crash again frame
great vid, i didnt understand the function on the top adjustment screw, the upper jockey wheel bolt is brushing against my spokes, may be this is the problem, or a bent hanger, or wheel out of true?👍
RJ what I'm really asking is if a derailleur has no B screw, how do you bring the cage pulley nearer the sprocket? Do I shorten chain? Do I replace a derailleur spring? Can I bend derailleur somehow?
I'd like to replace my original b screw on a 105 5800 rear derailleur with a longer one. Can you tell me how to turn it out completely? It seems as if there is some kind of stop which prevents it from being screwed out entirely. Nice work btw :)
Thanks for the great video RJ! One question: should this adjustment be done before or after the other derailleur adjustments (limit screws and cable tension)? Or does it not matter?
Thanks RJ; however, this Dura Ace rear derailleur's 'b' screw's entirely stripped on this vintage Bianchi. Can it be easily replaced? And is it compatible w/ the front Shimano R-1000? Any thoughts would be greatly appreciated. Actually, I'd like to change out the entire groupset.
For more bike repair videos hit the subscribe button 🛑 and click the notification bell ► bit.ly/SubRJTheBikeGuy
Hi my rear derailer is sitting to low when on smallest cog i adjusted the b screw all the way in but its still sitting to low and the chain is rubbing on the derailer please help.
I don't understand why some of the other rear derailleur videos fail to mention this. I actually had to search for this specifically to find this excellent video.
Me to 👍
I still can't find info on my 1970's Suntour version as the cog is always 2 inches from my cog! This is clearly one VERY misunderstood screw within the cycling world
A lot of them are trying to sell you a derailleur upgrade, oversized pulley wheel, oval chain ring, etc.. stuff you don't need. Seen it many times.
Same
Your backing out twice? I understand but your explanation is not correct.
B screw is often missed ,this is the best description on You tube .Given you a thumb.
I've been cycling for 10 years and this is the first time I've fully understood the mythical b-screw. Many thanks sir.
It's like the g spot?😆
Ill give mine a tweak tomorrow morning with your instructions, never really knew how to adjust it properly. Thanks RJ!
Just finished my first complete rebuild -an 80's Stumpy--total strip down,new bearings everywhere,etc--It's working very well and looks great too..Got it from a dumpster and now it's like a new bike..Your videos were extremely helpful...thanks very much and all the beat.
2:14 ah, I finally got it now, the space needs to be so the small deraileur cog moves individually from the bike's cogs without forcing one another into position. When they are too close the chain kind of forces one another into a fixed position.
Hell yeah! After months of cracking my head I finally got it! Got my Sram NX 1x11 drivetrain shifting like never before. Thanks a lot buddy! This was the fine tuning that I was looking for.
Same as my drive train hopefully I can sort mine thanks to this
Simple. Precise. Clear.
This is why RJ is my go-to RUclips bike mechanic. Never fails.
Oh man thank for explaining this in simplified terms. I liked the close ups and examples of what happens if it is not tuned. Keep it up
RJ has a video for literally every mechanical mess I get myself into! Thanks RJ, this is fantastic content
For me the B screw was my main problem for the sloppy shifting on my Shimano SLX. Thanks
Great tutorial! I feel like in every video people just say “ignore the b screw”. This really helped me remove the chain pinch/rub
This was very helpful. I bought a used bike that had the cog to close and the shifting was of in the lower gears because of that. I folowed your instruction and helped. Then I adjusted the cable tension got perfecly crisp shifting. Thanks!
Your videos are the go to source for me if I run into an issue I can't fix. Must have watched a hundred by now. Always informative, quick and clear, thank you so much RJ!
This is the simplest to understand video about this little screw that I found.
This guy explains things the clearest.
Thanks RJ, my bike would still be in tatters without your videos. You're a crucial part of my workout and self care routine!
I love RJ - he's been a real help on my European vintage(s) . Great Guy, period.
Nice one, I had mine set too far back after swapping frames and was getting erratic shifting and slipping in smaller gears. followed this and super crisp shifts again.
RJ The Bike Guy is my "go to" place to visit if I want to figure out how to set up or adjust something on a cycle. Absolutely brilliant videos - thanks RJ!
I always open a beer for RJ videos!!!! You are the best!!!!
Finally a video that shows how to fix the pinching, I had no idea. Thanks man!
Thanks! Now I know what I'm doing and why. The close-ups of the rear derailleur really helped.
Clear explanation thanks. Dunno why so many videos either fail to mention it or overcomplicate their explanation.
Thanks RJ nice precise video and no fluffing around. Funnily enough I have just brought a used Koga Miyatta and need to do this.
Thanks for this - I've never known quite how to know when it's set until now.
Keep up the good work.
within seconds I have understood the principle of the b-srew adjustment (allthough English is not my native language), thanks a lot!
Thanks for the info. It is needed when someone has been playing with the adjustments and got everything out of whack.
THANK YOU- BEEN TRYING TO FIND SOMETHING ON THIS FOR HOURS.
This worked great for me, RJ, but I had real issues with excessive shibbit when I was done. The solution was to align the hanger. Subscribed.
Ha! Shibbit.
Dude, your explanations are perfect
thx I discovered this makes big difference to shifting speed and accuracy- on my ultegra 8000 it was set way too far back and I was about to replace it - now sorted 👍
Your videos have helped me so much, thank you.
Wait a minute. I’m going to give this a shot. I just replaced my 11-34 to 12-42 today, but it was rubbing so i thought about getting a goat link which will take a few days upon ordering or local bike shops were close because it was late saturday now, since i found this video, i might give this a shot and hoping to test my bike at the trails after, thanks.
Thanks; I'd always wondered about that! Just changed from an 11-27 to something-32 tooth cluster, and new 105 GS cluster. Am now trying to tweak the adjustments. Your vids are a great help!
thanks so much just got a brand new bike shifting was horrible now shifts really good thanks
On a road bike rj you can get this thing dialed in great and make that shift crisp as heck man. I always adjust them at my shop for people and they all com back saying wow the shifting is so much better. When they are correct it's a big difference.
What if screwing in the b tension screw doesn't change the distance between cassette and tension pulley?
I'm reasonably good at adjusting my rear derailer but on my last tour no matter how I fiddled with it it would jump from 8 to 7 (9 speed derailer) when under heavy load e.g. on hills.I'd have to go all the way to 9 to stop this jumping. I couldn't reproduce the problem on bike stand or at the side of the road and with a light load it was just fine. In desperation I took it into a bike shop in Rolla MO. They were originally as mystified as me but after taking it out for two test rides they managed to figure it was the B screw adjustment. Adjusting the B screw so the jockey wheel so it was as close in as possible fixed the problem.
I would also look at these things: ruclips.net/video/VzrpC7jrz8U/видео.html
Peter Jack
It seems when you adjust gears on a stand it is fine for gear speed but not for representing chain tention or load.
Does chain tention relate to gear adjustment, should tention be done first.
Yes, same thing was happening to me, I thought it was the index, or indexing whatever.
Trek520 rider Most of the time 90% gear jumping is related to bad indexing after setting up the Low and High limit screws. The derailleur cable must have some tension when on the smallest cog. The indexing for the inner cogs is done through the Derailleur cable tension adjuster. What they told you is ridiculous and a complete lie. The only reason why you need to set the B screw is to stop the guide pulley from getting too close to the cogs causing noise and grinding issues with the chain.
Informative video. I have a question, does the B screw rest on the derailleur hanger?
B screw is also use to determine if you should use goatlink or not if you upgrade to bigger cogs like 11 42 from smaller one.
Hi RJ thanks for replying and helping out ..looks like the mech has twisted after i got hit from behind ...yer a top man all the best from Scotland
perfectly explained - least critical but worth to know - thanks for confirming what I've known by feeling
Problem solved instantly! Thanks man.
You just saved me a trip to the bike shop!
Thanks! In my case the derailleur seems to be to low when straightening the chain. Does this mean the chain is stretched? Thanks in advance.
Very Simple and Precise, Great 👍 Explanation
It may be, as you say, the least important screw on the rear derailleur, but if it's way out of whack (like it was on mine), it can make a huge difference when you're on the large cog. Thanks!
I learned this the hard way my rd cage was too slack because i didnt mind the b limit screw at all and the rd cage snapped while in a race and gotten last place but thank you for the tutorial this really helps
Request: a video describing in detail when it's time to change either of your casette, chain or chain rings - including tools used, etc. Thanks, and keep up the good work.
The chain, cassette and predominately used chainring (e.g. the middle ring on a 3 x setup) generally wear at the same rate on multi speed setups. 1 x drivetrain is a bit more of an exception because the narrow wide chainring teeth are usually taller and so you can usually get away with replacing just the chain and cassette.
You can usually tell if your chain and cassette (and possibly chainring(s)) are worn out because the chain will skip over the cassette under load, i.e. riding up a hill.
It used to be a myth that pressure washing your chain, cassette and chainring(s) somehow forced dirt into the system, thus wearing it out faster. That couldn’t be further from the truth! If you apply lube to your chain before pressure washing everything (be careful not to blast water into your wheel or bottom bracket bearings), dry the chain with a rag and re-oil it, you will vastly prolong your drivetrain’s life.
Man , I was having this exact problem. I was adjusting the high low screws cable tension no help, I couldn't figure it out, So simple thanks.
explained simple and logic.
well done.
Struggling a bit with my Shimano 11-speed XT rear derailleur. You state that the b-screw is not critical, yet I seem to have constant issues with the pulley rubbing the low cog, which is a 46 tooth pie plate!
The b screw seems very critical to these setups given the gap between the low and the second cog.
That's my problem.
Thanks for the video!
What do you do when the screw is all the way in but its still hitting ? Is it a weak spring that is in the housing that bolts onto the frame ? Will you make a video on how to chance that spring ?
Precise video , thank you .
Thanks man that noise was pissing me off but ur vid helped me fix it 👍
I bought the Garbaruk 11spd cassette for my 1x11 GRX rear der. I adjusted my B screw to handle the Garbaruk 46t cog from the Shimano 42t that I replaced. However I don’t feel like the Garbaruk shifts as smoothly as the Shimano HG cassette was. Now I kinda regret it and should have just got an XT cassette instead with the 46t cog
Bro youre amazing, not even freaking cycle lab could fix it😂 you’re literally the best
This is just what I needed because my derailer was pushed out and it was causing the chain to jump off! Thanks
Pushed out? Like bent out?
@@RJTheBikeGuy it turned out to be the gear cable that sets in the derailer. It was allowing it to push out instead of holding its place and the gears wouldn’t change. This video just kinda led to it and helped haha thanks!
Hi Jim here,
Great video.
I have an old bridgestone mb2 equipped with a 13X 34 7 spd cassette and a shimano xt long cage rear derailler. The upper guide will always hit 34t gear even when b screw fully screwed in. Even installed a longer b screw where it still upper guide will hit 34t gear when fully screwed in.
Is the pivot spring worn out? Do I clean derailler pivot bolt by disassembling. I have 15 other bikes using the 13x34 7 spd set up where most all work perfectly.
Any ideas 💡?
Thanks,
Jim-
Short, simple and correct answer to B tension screw adjustments. Thanks man! Bike is set up properly now!
finally, someone explain what a b screw is 👏👏👏
hey, should you also be able to pedal backwards without noise? Because my B-screw is all the way in and I can still hear some unpleasant sounds.
Thank you, now i know. And thank you for all the other videos. Thanks from Norway:)
You make helpful useful videos, thanks a lot
Thank you, swapped out cassette that had a slightly bigger cog as the biggest one and this fixed it :).
Small tip: While you are turning the screw, you pull the RD slightly away so that the B tension screw isn’t pressing firmly onto the B link or the RD hangar. And you check periodically whether or not you got the correct spacing. (Now if your bike is new or your RD is new, Shimano and SRAM gives you an indicator, so finding the correct spacing is a lot easier for rookies, you no longer need to eyeball or use a ruler.) The reason being is that the tip of the screw is very hard, and is often rough. So that it can very easily grind a divot into your hangar or B link, especially when you are doing that first time, and you are turning the screw back and forth.
thx
Just got a new hyper eride mountain ebike with Falcon derailer , dont know knothing lol. Is this screw also the way to tighten the chain ? or is the only way to tighten the chain remover links? Thanks
Very informative n useful vdo thank you a lot for sharing 👍
Love your video, easy to understand
Great video, man! I can enjoy my new 11-32T cassette!
I was hearing a crunching sound when I went up a hill in my lowest gear, or biggest cassette ring of 34.
Adjusting the B screw solves the issue I think.
The pulley was too close to chain ring.
It's the least critical adjustment, but it t can solve some unpleasant noises.
My B screw doesn't seem to do anything when adjusted. I have a Shimano tourney set up and it's got this very tall 1st gear and the cogs are slapping against each other, I'm getting that exact grinding shown here because they are too close together.
If you were to put all the video's on bike repairs into a DVD or for upload online, I would buy it IMMEDIATELY for my collection!
Have a Shimano Tourney Drailler and it is to close to the first gear, and the screw is all the way in. Is there a fix for this. or will I have to replace the derailler and what would be a good one to go to, as this none is not very old and was not used a lot.
HELP! My shimano SIS lacks the B-screw and the pulley makes contact with the larger gear of the cassette.
Peple are suggesting to adjust the housing lenght to avoid that. Does it really work? And how to measure it?
Thanks!!!
This is a description of how to shift up the best. You should also consider having the cage far enough away from the cassette when in the 2nd to largest cog to clear the largest cog when shifting down.
you deserve my thanks
It's not clear which way turning the screw CW or CCW makes the adjustment. when he was "backing off" was he actually screwing in or screwing out the b-screw. It's not clear from the video.
Thank you for this!
excellent derailleur tutorialll
Super helpful, thanks. At my coop we typically just completely ignore the B screw haha
Thanks RJ! Great video! You just saved me :)
Great explanation. Thank you
HI. I have a suntour derailleur model EDGE 4050, I dont know if is missing a little plastic cube, . It seems this derailleur doesnt have a B screw or something . In the moment I mount chain... there is nothing that stop it, crash again frame
great vid, i didnt understand the function on the top adjustment screw, the upper jockey wheel bolt is brushing against my spokes, may be this is the problem, or a bent hanger, or wheel out of true?👍
Most likely limiting screw adjustment, bent derailleur, or bent hanger.
@@RJTheBikeGuy 👍many thanks
Thank you you're my hero
Great explanation.
Problem solved. Thanks for that !
Nicely explained
RJ what I'm really asking is if a derailleur has no B screw, how do you bring the cage pulley nearer the sprocket? Do I shorten chain? Do I replace a derailleur spring? Can I bend derailleur somehow?
I can't tell you without working on the bike and see what is there and how it is set up.
Fair enough man, love your content btw. Tis a great resource thx :)
I'd like to replace my original b screw on a 105 5800 rear derailleur with a longer one. Can you tell me how to turn it out completely? It seems as if there is some kind of stop which prevents it from being screwed out entirely.
Nice work btw :)
Cut off the end of the screw.
+RJ The Bike Guy Ah thank you! I wasn't quite sure about that. Keep up the good work :)
Thanks for the great video RJ! One question: should this adjustment be done before or after the other derailleur adjustments (limit screws and cable tension)? Or does it not matter?
Doesn't matter so much.
Thanks.
Thanks RJ; however, this Dura Ace rear derailleur's 'b' screw's entirely stripped on this vintage Bianchi. Can it be easily replaced? And is it compatible w/ the front Shimano R-1000? Any thoughts would be greatly appreciated. Actually, I'd like to change out the entire groupset.
If the screw is stripped, replace the screw. If the threading the derailleur is stripped, I don't think it can easily be fixed.
Your a Legend! 🤩
thank you legend!
Very useful thankss
Will this adjustment help fix the slight sag in my daughter’s chain? When she goes over a bump her chain shakes a bit.
Maybe. Maybe not. Could be worn chain. Worn derailleur. Chain too long. Or something else.