I was replacing my chain for the new season and decided to give my rear derailleur (Shimano Ultegra, 4 years old) a bit of a cleaning since the chain is off (nothing more than just a wipe down of any extra grease/residue from what accumulated on it since the last time I cleaned the chain). While doing that I noticed that one of the cogs rotates freely: if I give it a spin - it keeps going for a second or so. Another one is a bit tighter - i can rotate it manually, but it does not spin after I let it go.
Does this seem normal/is this a big deal? I’d expect both to spin pretty easily, otherwise it seems that friction would be causing a few watts to be wasted.
That doesn’t sound terrible…the pulleys are so light that they don’t really “spin” after you let go anyway.
But at 4 years, you might just throw on a new set of pulleys. They’re cheap enough, and they are considered a “consumable,” i.e. something that’s not intended to last the lifetime of a heavily used groupset.
on Ultegra, one jockey wheel is a bushel (top I think) and one is a cartridge if I remember right. the bushel one doesnt spin that freely. try popping the pulley off, take the cover off and clean the bearing area and screw. grease the screw nicely and the bearing cover and reassemble. should held free them up a little.
on Ultegra, one jockey wheel is a bushel (top I think) and one is a cartridge if I remember right. the bushel one doesnt spin that freely. try popping the pulley off, take the cover off and clean the bearing area and screw. grease the screw nicely and the bearing cover and reassemble. should held free them up a little.
Yeah, Ultegra is one bearing and one bushing. The irony is that the bushing (assuming it isn’t clogged with goop) will spin more freely than the bearing (which has some drag from the seals). Under chain load though, the bearing is far more efficient.
Personally, I usually upgrade my jockey pulleys to aftermarket ones with bearings (usually in some bling color to match my bike): http://www.ebay.com/...acat=0&_from=R40
That is exactly it. The upper pulley uses a bushing which, with miles, grit, and a lack of lubrication, get pretty slow and sticky. The lower pulley uses ball bearings, and it usually spins easily, even after lots of miles. The easiest solution? Replace both pulleys with some inexpensive sealed bearing tacx pulleys, like these guys.
I noticed this too a few months ago when replacing the chain on an bike with ultegra RD which is less than a year old and well cared for.
I dismantled and cleaned the bushing bearing and it made barely any difference. It was a quick and easy job though.
I did not dismantle the ball bearing one as last year I had a nightmare dismantling a Durace RD with bearings. Ended up with pin head sized bearings pinging out which were a nightmare to get back in place !
In future I will upgrade my jockey wheels as others have suggested. I can’t remember where I saw it but I did once read an article saying you could save a watt or two with better ones…think there is a web site for a company that has analysed drive train losses…might have been a link on Jack Mott’s page.
Thanks folks. Took the upper pulley apart (turns out it’s a ceramic bushing one) gave it a thorough cleaning/degreased/relubed and put it back together. Now it rotates much smoother than before.
Couldn’t re-install the seal rings for some time, but finally put them back in. A bit concerned, because I don’t see anything holding the seal rings in place (and it seems that they could easily pop-out). For now everything is in-place,but will keep an eye on them to make sure nothing falls out.
