Velo Vol 

I have my chain off for the first time [3,300 miles on Ultegra 10 speed]. I see that while the "bottom" pulley on the rear derailleur turns easily, there's noticeable resistance when I try to spin the "top" pulley (the one nearest the derailleur).

Is this normal? If not, what's the likely cause?

Psychic Pimp

The derailleur pulleys have bearings that, like all bearings, require periodic maintenance. Take them apart, clean and lube them. If they are too torn up or crusty inside, replace them. The more expensive derailleurs have cartridge bearings there, the cheaper ones have a simple bushing sleave. For the bushing type, this is a good place for a drop or two of Tenacious oil and/or chain oil when you lube the chain.

well biked

Before I'd take anything apart, I think I'd clean the pulley wheel with a rag, and then drip some chain oil on it, allowing the oil to penetrate on both sides to the little bearings, spin it with your fingers, and then wipe off any excess oil. It'll probably spin like brand new.........Then, as Psychic Pimp says, oil it occasionally thereafter-

San Rensho 

Spray WD40 into it with the narrow tube while spinning, spin some more to remove excess, put lots of oil in it while spinning, wipe off excess. Do the other one while you're at it.

Ivan Hanz

Removing and cleaning rear pulleys is one of the easiest and most enjoyable maintenance tasks out there. Give it a shot! Let nary a pulley squeek!

Ed Holland

If you do remove the pulleys, be sure to replace them correctly, since they are different. The top pulley has more lateral play than the lower, I believe, in order to improve the behaviour of indexed shifting systems.

Cheers,

Ed

Eatadonut

I put a few drops of whatever chain oil I'm using in the pulleys whenever I clean the chain.

jasond

I just received a new Ultegra 10 speed group from probikekit.com and the ceramic bearing on the rear derailleur (the top pulley) is quite stiff when compared to the bottom one. Is this normal in a brand new derailleur? Is it something my bike tech can adjust when he builds the bike?

rmfnla

Probably is stiff from the factory grease and just needs to "break in".

This is not an adjustable part.