This is on an 80's Peugeot, with 6 sp freewheel, Shimano Tiagra derailleur, and friction shifting. I took it apart to clean and didn't note which was which, thinking they were the same. If I were to guess, the narrow one (right) goes closer to cassette since it has less of a bearing? The other (left) going "outside" with chain load from front ring coming into it.
Anyone know for sure?
#BikeTooter #bike #VintageBike
G / guide / Centeron pulley is the upper one closest to the cassette.
Narrow is the tension pulley, down on the chain.
@isol totally guessed wrong, thanks!
Also, with bushings, washers etc., the upper / guide pulley has slightly more side-to-side movement than the lower / tension one.
@jerzone Note to self: Take photos of "everything" when pulling things apart!
@LovesTha I have photos of the things that never needed a photo. This was certainly too obvious to need a photo. 🙃
May 12, 2026, 3:34 AM@jerzone the one closest to the cassette takes the most axial load and so needs the bushing... Is how I remember it anyway
@g That's a good explanation of why it's like that.