# What is a G-pulley?



## bmwjoe (Jul 15, 2012)

Last fall I put a new Shimano 105 rear derailleur on the bike and last night I decided to pull out the pulleys and clean and lube them. I was very careful to not mix them up when taking them off. I then held them against each other and saw they were the same diameter and tossed them on the parts washer. 

I take them out and I see they are indeed different. Oops. One pulley has a metal bushing and one does not. The one with the busing was marked G-pulley and the one that was all plastic just has a rotation arrow. 

I have never heard of the term G-pulley. Is that the same as the jockey pulley, which is the one closest to the cassette? An I correct putting the pulley with the bushing in the position closest to the cassette?

Ride Safe,

Joe


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## Jay Strongbow (May 8, 2010)

The one with the bushing goes on top. It's pretty easy to over tighten it so make sure it spins freely and there is some side to side play (the side to side play is the key difference between the two).


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## Love Commander (Aug 20, 2009)

G-pulley is probably the guide pulley - and yes, it's the one that's closest to the cassette. The other will be the tension pulley

User manual here, referencing guide pulley and tension pulley, with torque specs for re-installing them (pdf)


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