My jockey wheels are so worn they are “pointy”. My gears in the lower end of the cassette jump despite all my attempts as sorting them out.

Could it be the jockey wheels causing it ?

Just want to check first cause I’m too skint to order a mech, so will try the jockeys if its likely to be them.

Cheers all.

yep

less likely than a worn chain/cassette.
jockey wheels can be worn beyond belief before affecting anything.

Banged your mech ?? Out of line mech / worn chain / worn cassette are most likely to be what it is. Worn Jockeys, annoying though they are, will just tend to mean slow / crap changing.

Sounds like you’ve just put a new chain on…

No.

You’ve just changed the chain haven’t you? If your chain gets more than slightly worn it takes the cassette out with it. The old chain and cass will work fine with each other for a long time but if you change the chain it’ll skip like hell.

New cassette.

Chain and cassette were purchased and fitted together some 6 months ago. I have a chain wear tool and the chain is fine.

I have changed the cable twice.

Its doing my head in proper. I set it up on the workstand and its working fine, but give it 2 rides and its skipping all over the place in 2nd, 3rd, 4th gears. Only does it in the granny ring, If I shift into the middle it doesnt jump.

If you’ve changed the chain and the cassette then it coule be worn worn jockey wheels or a stiff link in the chain. Back pedal to see where the chain is catching then check the links first. A worn jockey wheel will cause the chain to jump though, last time I changed my chain/cassette I had to chainge the lowere jockey wheel as it was ninja death star stylee. But I had done around 8000 miles on that jockey wheel.

Yeah mine are like that.

Anyone know where I can get jockey wheels at a reasonable price ?

I check CRC but they want 21.99 for a pair!!!!

I can get a new bloody mech for 31 from Merlin.

£21.99 a pair!! I got some fancy pants ceramic blingtastic gold ones for less than that. £10 from your lbs or Tacx for £14.

spikey jockey wheels won’t affect it but side-to-side play might. take the chain off and give the guide wheel a wobble. if the bearings are nackered there will be a lot of sideways movement which will definitely cause sloppy shifting and probably isn’t helping the chain run straight on the cogs. but check your high/low screws and cable tension are set properly first.

Tim

spikey jockey wheels won’t affect it They will if you put a new chain on. The chain won’t mesh with the jockey wheel properly.

if the bearings are nackered there will be a lot of sideways movement

There’s meant to be side-to-side movement in the top one (guide pulley). In fact, Shimano patented this (the floating jockey wheel) and on XTR they make nifty sealed cartridge bearings with play built in. It’s how they make indexing work – without it, you’d get rubbing and clicking if your indexing was a tiny fraction out or there was any slight crud in your cables.

Ive had this, the little wheels had bugger all to do with it – so long as the move freely.

Try a new outer as well as a new inner cable.

Hmmm… 2 good posts there lads. The chain and cassette were put on with an old mech, so that might be it. Also good point be bomberman re the side to side play. I’ll give that a look see tonight.

So anyone point me at some cheap jockey wheels ? Mech is an XT rapid rise 761.

molgrips – Member
There’s meant to be side-to-side movement in the top one (guide pulley).

My chain was slipping/dropping out of gear because there was too much movement in the top Jocky. swapped with bottom and problem was solved.
Keep them clean!

Pointy jockey wheels won’t cause chain skip in my experience – I ran a pair until they were rollers rather than sprockets – ie no teeth left at all – new chains and cassettes a few times. side to side play might cause issues but I doubt it.

Okay from my personal experience – changed the chain and cassette, chain skipping – did all the usual checks for stiff link etc. Lowere jockey wheel very pointy. Replaced this and skipping etc stopped. So from my personal experience a worn jockey wheel can cause skipping with a new chain.

Get on your knees and look at the actual gears from behind. If the jockey wheels are in line with the cassette, how will they cause it to skip. They are only there to take up chain slack.

If they are not in line and there is no side to side tolerance then this is a mech / hanger / indexing / cable issue. Jockey wheels are not the issue.

I must have imagined it then.

If the jockey wheels are in line with the cassette, how will they cause it to skip. Because the chain isn’t meshing with the jockey wheels.

JON, spot on mate. I’m not gonna argue with a bunch of idiots on here, i’ve said what i think it is so lets see what happens

Trimix – Member
Get on your knees and look at the actual gears from behind. If the jockey wheels are in line with the cassette, how will they cause it to skip. They are only there to take up chain slack

Rubbish! the lower takes up slack of the chain. The upper directs the chain on to the cog, how else do you suppose changeing gear. if the upper cog has enough play/is not close enough to the cassette cog then it can fall out of gear. As Gary-M says it can happen. Granted you primarily need to make sure you gears are set up correctly.

Credit where its due, bommerman you were first there. 🙂

bomberman has spoken – I’m clearly an idiot.

Gary_M ?
Are you and bommerman and I not all in agreement?

swapped with bottom and problem was solved

Er dunno what you’re riding but the top and bottom pulleys on Shimano are different and the bottom won’t fit on the top since it’s got a thicker shoulder.

Because the chain isn’t meshing with the jockey wheels.

If by skipping we mean slipping over the cassette teeth like when you put a new chain on a worn block, then the jockey wheels don’t have any effect. That kind of skipping is caused by the chain lifting off all the teeth on the sprocket, and would still happen even if you removed the rear mech entirely. It’s all between the chain and the sprocket. The rings, top run of chain and chainrings are the only bit under tension.

You could actually fit rollers instead of jockey wheels and it’d still not skip.

However, if you are talking about the chain picking up on a higher or lower gear, that’s a different thing. If your indexing is out then the chain will be trying to shift one way or the other whilst making nasty clicking sounds, and some partial jumps. It’ll either go away or shift if you part-press the shifter. Worn jockey wheels COULD cause that but only if they were almost totally smooth. I’ve ridden pointy ones for many hundreds of miles with no ill effect. If there’s too much play in the top jockey wheel then it would make your shifting worse but hard to see how it would cause skipping. Plus, knowing how the bearings are in jockey wheels, it’d have to be incredibly worn to be doing that – the ceramic bushings (or cartridge bearings in higher end stuff) would have to be worn conical on each side which is extremely hard to imagine.

I’m not an idiot thanks bomberman, I just know how to fix bikes 🙂

Has the OP checked his chainrings for wear?

I dunno, he said ‘spikey jockey wheels won’t affect it’ which I disagree with, but the idiot comment, whoever it was aimed at, was a bit strong.

it can fall out of gear

Well I’m sceptical about that since there’s no lateral force on the chain between the jockey wheels and the cassette. So what would cause it to move sideways enough to come off the sprocket? Your mech would have to be an absolute flappy sloppy mess the like of which I’ve never seen (and I doubt if it’s even possible before it fell apart) to let the chain jump out of gear spontaneously. I’ve ridden with some sloppy-assed mechs before and had perfect shifting.

Looks like you will just have to go single speed as no one can agree on a solution 🙂

I’m not diagnosing the problem absolutely, there is a lot going on at the derailleur and many items can be adjusted to fine tune your shifting. I’m just saying that with a sloppy upper jockey mygears was skipping and wandering off the cog. By changing it (molgrips, I may have swapped it with another jockey) the problem was solved.

They wear out and you replace them, my changes have always become worse with worn jockeys.
It can cause jumping especialy if the B stop is badly adusted.
But dificult to diagnose without seeing everything else, the way I always see bike mechanics is that it’s not rocket science, keep it all in good order and condition and it’ll always work IMO.
Top and bottom jockeys are different again IME.

That kind of skipping is caused by the chain lifting off all the teeth on the sprocket, and would still happen even if you removed the rear mech entirely.

molgrips – i said i wouldnt argue with you but i’m gonna have to put you straight. if you have a rear mech failure on the trail and need to remove it then the golden rule is to always run the chain on the largest sprocket of the cassette before you cut it down to size. The reason for this is that the ramps on each sprocket are designed to push the chain upwards to aid shifting. If you were to cut down the chain to the smallest cog and try running singlespeed like that you wouldn’t get very far as the ramps try to push it up onto a bigger cog – your chain would snap. I’ve no doubt you’ve never even tried running a bike without a rear mech otherwise you would’ve known that out of experience.

as you are a bike-fixing wizard i’m sure you can now figure out why a sloppy guide jockey wheel could cause skipping.

Tim

The ramps on the gear are there to catch the link plates as they are pushed over by the rear mech. Unless you’re running a wildly incorrect chainline they wont do it without the aid of a mech. I’ve run a normal block and chain tensioner with a granny for years on my trials bike. The only way the ramps aid shifting is to help guide, not actively snatch the chain and move it. The only time the trials bike jumps up a gear is if I put it in the lower cogs, this is because you’re effectively in granny and small – not something you want to do with any geared system due to the lateral movement in the chain line it produces. This is why they suggest a trail-repair goes onto the top cog, if you’re setting up from scratch and not using extreme chainlines you can use any gear you like and it wont skip upward.

Worn teeth on your mech will only cause it to skip within the mech, it wont cause it to jump over the block under power. Lateral play in the top jockey will screw up your shifting and cause ghost shifting. Bottom pulley might as well be a rubber ring.

Bomberman, you are correct, but that’s due to the chainline of a chain without a rear mech. Even worn a mech would still bring the chain into alignment mostly. My point still stands that with a mech even with worn jockey wheels you won’t get skipping unless the indexing’s adjusted out or the mech is very very very floppy. If you had no teeth at all on the jockey wheels you might also suffer.

But again, the OP’s problem depends on what he means by skipping. Either the chain being caught on the adjacent sprockets or the chain jumping over the teeth.

I’ve ridden loads with very worn jockey wheels and had no skipping. So what does that tell you?

as you are a bike-fixing wizard i’m sure you can now figure out why a sloppy guide jockey wheel could cause skipping.

It’s because I’m such a bike wizard that I already have it figured out… 😉 Lighten up fellas.

i’m not saying the teeth being worn is the problem, i reckon it’s play in the guide jockey wheel. they don’t call it the guide for nothing! I think the OP should report back and put us all out of our misery (once he solves the problem by replacing the jockey wheels) 😉

Yeah.. I wanna know what kind of skipping it is before I diagnose*

* Molgrips’ diagnoses are guaranteed to be 100% correct

er… right…. thanks.

I go for no, I have run road Jockey wheels down and not had an issue. at the end of the day tension, chain stretch etc is a likely cause. Only the top jockey wheel could have an effect on the shifting and even then on a small cog as long as mech is adjusted to fold around the cassette correctly the chain should be wrapped well around the cassette. As such, never seen the difference a jockey wheel would have unless there was loads of lateral float would be hard to understand unless the actual plates were loose.

looks like ‘yep’ is the answer to me

christ lowey how do you get such a reaction?
Personally I just think it cannot cope with the awesome power unleashed when you pedal ease back a bit

thought I would add another suggestion there as we dont seem to have reached 10 possible answers yet