wrr1020

So recently i noticed my chain seems to get caught up on one of the rear derailleur pulleys. Noticed it on a ride a couple days ago. I'm terrible with tuning derailleurs and before i bring it to my LBS i wanna try and fix this myself. I'd love to learn these things and not rely on my LBS for a job like this. I'll upload a video into this post. Shifting from high to low while on the big ring the derailleur skips a gear or two and overall its just in bad shape. Also when trying to take the rear wheel off it basically won't come off, one of the pulleys seems to be in the way and don't want to force it off.

Not many miles on the drivetrain, bought the bike new in January online. Components are full SRAM Force. Sorry the video isn't the clearest, was taken indoors with my point and shoot camera. If anyone can help me out on what screws to turn and what way to turn the barrel adjuster i'd appreciate it.

EDIT: Forgot to mention the symptom in the video only happens in that gear, its the second to the biggest cog on the rear.

View My Video

BotByte

I had the same problem, my fix: Single Speed!

You have a dead set of links in your chain. I advise to get a brand new chain and have a LBS install it and make sure that they completely work over the new chain and check for dead links in the NEW chain.

ultraman6970

Don't want to be mean but it is just thing of moving the screws and look what the RD is doing, is not rocket science. I'm sure nobody told you how to use a condom, but i bet U knew what to do with it right away, yes???.

This is almost the same thing, move the on screw and see what happens, move the other screw and see what happens. I'm not even familiar with sram but clearly the screw that says H needs to be tight (i believe) like half a turn. Again im not familiar with Sram but pretty much thats what u have to do.

RD adjustments is a thing of common sence. The screw moves left the rd will do something, move the screw to the other side and the rd will do the opposite. Is not like putting together the rubik's cube.

If you are in DC metro area I can fix it for you for free but u have to bring the bike to me.

Good luck.

MrTuner1970

Go to Park Tool's website. Read/watch how to adjust a RD. The solution is most likely adjusting the tension of the RD cable. Would take only a few seconds to adjust.

climber7

if you want to do it yourself, read these two things, the second of which is what MrTuner mentioned:

https://www.sheldonbrown.com/derailer-adjustment.html
https://www.parktool.com/blog/repair-...nts-derailleur

i read those and was able to adjust my derailleurs in about 5 minutes.


this is not correct. for the front derailleur, yes, you adjust with the limit screws. for the rear, you shouldn't need to change any of the screws unless something else changes - e.g. different length chain, maybe different wheel/cassette, etc. normal tune-up should just involve the barrel adjuster.

EDIT: just watched the video and it looks like something funky is going on with the chain even when you're not shifting the RD, so i guess there might be something else going on. not sure what, though.

JonnyV

OK, before my ambien really begins to kick my ass (I can say ass) here's how you tune your RD. Assuming it really truely needs it. Shift into your highest gear (large chainring, small cog). Is your RD cable loose? Fine. Loosen the bolt that holds the cable. Check your high limit screw, the pulley should be directly below the smallest cog (the one you put your chain on). If it's to the outside of the cog, turn the High limit screw clockwise slowly until the pulley is directly below the cog. This will be the same at the other end of the cassette. Now, take the barrel adjuster on your RD and turn it in all the way. Done? Good, now back it out 2 full turns. Stop touching that. Pull the slack out of the cable, pull it kinda tight. Tighten that bolt so the cable can't slip back thru. Go thru your gears. Check the limit screw at the low end, make sure the pulley is directly below the largest cog. If the pulley is to the outside of the cog either fix it or start saving for a new rearwheel, chain, RD.

fly:yes/land:no

no amount of responses to this thread will teach you as effectively as you just messing around with the thing yourself. i promise, you won't break it by turning the barrel adjuster.

Sixty Fiver

Turning the barrel adjuster to and fro won't harm anything... messing with the limit screws could cause the chain to ride up into the spokes or jam against the dropout.

That high pinging I hear in the video sounds like the derailleur brushing the spokes and my suspicion is that the derailleur hangar may be just a little bent and until you know that for sure there is no point in trying to set up the drive train.

fly:yes/land:no

i agree with everything except this statement. when your shifting gets a bit funny, do you look to see if the derailleur is bent, or do you adjust the cable tension to see if you can remedy the problem? on my checklist, checking the hanger is the last thing, not the first.

Campag4life

Pretty ominous noise in the middle of the vid. The video really lacks perspective but there is likely nothing wrong with your driveline...you mentioned it is relatively new. It is way out of adjustment and the chain is literally between cogs in back and why it is jumping. If the rear derailleur shifts fine and chain tracks properly on the smaller cogs of the cassette but as you shift up the cassette adjustment on the big cogs is way off as you show, this means your rear derailleur hanger is bent...common. You need to check if the hanger is bent yourself with a Park gage or take it to a shop and have it checked. Most with a schooled eye can see the derailleur hanger is bent by seeing if the pulleys of the derailleur cage run parallel to the cogs on the cassette.
Don't ride the bike this way in case you don't know.
Good Luck.

Sixty Fiver

I come at this from someone who does this for a living and am dealing with other people's bikes far more than I have to deal with my own... it only takes a minute to check a hangar during an inspection and it is a very common thing to see.

fly:yes/land:no

okay... i come at this from someone who has also done this for a living. i am well aware of the frequency of jabbed up hangers. i am also aware of the frequency of cable tension issues. you are really going to ask a guy who has seemingly no idea how set screws work to look for a bent derailleur hanger? i think we both know that spotting a bent hanger (let alone fixing it) is much more difficult than spinning an adjuster a few clicks clockwise or counter clockwise.

you are certainly correct that it could be bent, but why wouldn't he at least try to adjust the cable before calling the shop? this comes with the obvious caveat that if the derailleur is in fact what is pinging the spokes, then there is a lot more wrong than cable tension.

Homebrew01

I don't think the pinging was from the RD hitting the spokes. It wasn't on the largest cog, and it wasn't consistent (still worth double checking though)
Looks like just a bit too much cable tension causing the RD to try and shift up to the next largest cog.

liquefied

You're an LBS's wet dream.

Sixty Fiver

This is what I do in real life... making remote diagnosis is a pita as not only can you not really see the problem you have to deal with people who don't understand what the problem is.

Most of the time I give lessons in theory instead of trying to diagnose a problem with less than stellar pics or inadequate video as once you have the theory doing the work becomes much easier.

Lots of folks said to adjust the derailleur... this is good advice.

Park has excellent instructions on how to do this.

Had to point out that if the hanger is bent it will be a waste of time so to look there first to ensure it is reasonably aligned.

If a chain has a stiff link it does not have to be replaced... a little gentle side to side flexing usually addresses that.

wrr1020

So i messed with it all of last night practically and i just couldn't get it dialed in correctly. It would shift to the smaller cogs just fine but shifting from smallest to biggest cogs it would jump a gear or two. Finally took it to the lbs and he was able to adjust everything and get it set up properly. Got rid of the chain snag from the video and fixed my shifting. Even though i didn't fix it i came away with knowing more about rear derailleurs and what screws do what exactly. If something like this happens again or theirs some kind of missed shift going on i'll feel more comfortable "trying" to fix it. Thanks for all the tips and suggestions.

liquefied

That's good. I believe everyone should know how to adjust their own derailleurs. It's not terribly difficult but can look daunting when you don't know what you're doing.