Question about jockey wheels. I was cleaning my chain today, and decided to give my jockey wheels a proper clean. I normally just give them a quick brush with a tooth brush, but having some spare time today, thought I'd take it all apart, and do it properly. When I removed them, I noticed that they're not actually the same. One has a bearing, and the other doesn't. I didn't make this discovery until after I mixed them up (surprisingly), so don't know if the top or bottom one had the bearing. Any thoughts? Does it really matter?
Question about jockey wheels. I was cleaning my chain today, and decided to give my jockey wheels a proper clean. I normally just give them a quick brush with a tooth brush, but having some spare time today, thought I'd take it all apart, and do it properly. When I removed them, I noticed that they're not actually the same. One has a bearing, and the other doesn't. I didn't make this discovery until after I mixed them up (surprisingly), so don't know if the top or bottom one had the bearing. Any thoughts? Does it really matter?
Peter.
The one w/ bearing goes on top. Notice also that the 'design' of the jockey wheels are not identical (well at least on campy records).
Just to clarify, "w/" is with, not "with out", correct?
correct
Also please use the attached as a reference. The upper can be used for even the lower but not vice versa - it will still work but you lose some shift "crispiness". The upper pulley works harder and is subject to higher forces than the lower necessitating the need for it to be more accurate and robust ie. bearings.
FWIW I replaced both my stock jockey wheels with aluminum ones which are identical to the stock plastic upper. These feature cartridge bearings and hard anodization.
Also please use the attached as a reference. The upper can be used for even the lower but not vice versa - it will still work but you lose some shift "crispiness". The upper pulley works harder and is subject to higher forces than the lower necessitating the need for it to be more accurate and robust ie. bearings.
FWIW I replaced both my stock jockey wheels with aluminum ones which are identical to the stock plastic upper. These feature cartridge bearings and hard anodization.
Just to nit pick here - the upper one is the jockey pulley (because it jockeys the chain from cog to cog) and the lower one is the idler or tension pulley and it just keeps the chain from sagging on the bottom.
Just to nit pick here - the upper one is the jockey pulley (because it jockeys the chain from cog to cog) and the lower one is the idler or tension pulley and it just keeps the chain from sagging on the bottom.
To continue the nits, don't both pulley's have bearings? On the Shimano stuff I have, the jockey pulley has lateral float built in, the idler (bottom one) doesn't. That's the way I tell them apart.
To continue the nits, don't both pulley's have bearings? On the Shimano stuff I have, the jockey pulley has lateral float built in, the idler (bottom one) doesn't. That's the way I tell them apart.
Depends on the brand/level. Campy uses a bushing on the lower pulley instead of a ball bearing for their upper level derailleurs. The radial loads on the lower pulley aren't as high, and it saves a bit of weight.
Make sure that you use a decent thread lock if you have a model of derailleur that uses a bolt when you replace it. We had the bolt fall out of our upper jockey wheel which caused the chain to jam which caused the derailleur to head west through the wheel which broke spokes on both sides of the wheel and also bent the dropout into an interesting shape. This happened on tour 30kms from the nearest town. The deraileur was an XTR. I have noticed that the latest model uses a circlip.
I managed to replace the 4 broken spokes, find the jockey wheel and hold it place with a bolt made from one of the broken spokes and straigten the dropout enough to get us to the next town wit ha decent bike shop.
Make sure that you use a decent thread lock if you have a model of derailleur that uses a bolt when you replace it. We had the bolt fall out of our upper jockey wheel which caused the chain to jam which caused the derailleur to head west through the wheel which broke spokes on both sides of the wheel and also bent the dropout into an interesting shape. This happened on tour 30kms from the nearest town. The deraileur was an XTR. I have noticed that the latest model uses a circlip.
I managed to replace the 4 broken spokes, find the jockey wheel and hold it place with a bolt made from one of the broken spokes and straigten the dropout enough to get us to the next town wit ha decent bike shop.
Cheers
Geoff
This made me think to bring along an extra pulley and bolt (along with the ususal stuff I bring along) next time I go on a long trek. There's always a first time such things happen to cyclist.
