Stone 12s Pulley Wheel Gear Guide Roller Jockey 10t 12t 14t 16t Bearing Road MTB Bike Rear Derailleur for GX XX1 for Shimano M9000
Name: Stone Pulley Wheel, narrow wide tooth
Material: POM high strength resin, NSK bearing
Bearing: Japan NSK 689-2RS
Tooth: 10T/12T/14/16T
Fit for most brand chain of 8 9 10 11 12 speed.
But not work for Sram brand road bike 12s chain axs flattop chain.
See below if you have for Shimano brand 12s road bike chain:
You have to remove the original chain quick link if you want work for shimano brand 12s road bike chain. change the quick link to any other brand quick link will works. Reason is, the original quick link for shimano 12s road bike chain is too narrow, but change to other brand 12s quick link will let it works and fit to this pulley.
Weight: 9g/10g/12g/15g
Thickness: 8mm
Inner diameter: 6mm (compatible with 4/5mm)
Color: black wheel with black cover, black wheel with red cover
Advice and principle to customers who want to modification:
1. top pulley called guide pulley, size should be smaller then lower pulley, as if too big then it will hit the cassette flywheel. the max size you can buy is 1 tooth bigger than you current use.
2. Big size means more likely to round, but only recommend increase 1 tooth base on your current pulley size for the top guide wheel, if too big, the top guide wheel will hit the cassette flywheel.
the lower tension wheel, you can add 1-2 tooth base on the size you current using. as big size means more like to round, it will help riding.
3. If you are single chainring, recommend change to narrow wide tooth. Performance will better.
For example,
if your top guide wheel is 11T, the max you can change is 12T. 13T is too big for you.
the lower tension wheel you use is 11T, you can change it to 12T or 13T, any is fine.
Tooth OD(mm) Weight(g) Fit for
10T — 43.1mm– 9g — Short arm leg
12T– 52mm — 10g — Most middle and long arm
14T — 58mm– 12g — Some long arm
16T — 65.5mm– 15g — Very less long arm
Polyoxymethylene (POM), also known as acetal, polyacetal, and polyformaldehyde, is an engineering thermoplastic used in precision parts requiring high stiffness, low friction, and excellent dimensional stability.
POM is characterized by its high strength, hardness and rigidity to −40 °C.
Typical applications for POM include high-performance engineering components such as small gear wheels, eyeglass frames, ball bearings, ski bindings, fasteners, guns, knife handles, and lock systems. The material is widely used in the automotive and consumer electronics industry.
Package:
1* pulley wheel, 1*bolt adapter for 4mm to 6mm, 1*bolt adapter for 5mm to 6mm
if buy 1pcs pulley, you will get 1pcs and the small parts.
if buy 2pcs pulley, you will get 2pcs and the small parts.






