Bicycle Rear Derailleur b screw adjustment

The b screw adjustment is required when either:

1) In the largest cog, there is an issue with chainsuck (when the chain wraps around the largest cog instead of going directly to the rear derailleur), or

2) one experiences shifting issues in the smallest cogs.


As a general rule of thumb, the b screw should be about 6 mm away from the largest cog.


Step #1 View the b screw on the back of the rear dérailleur ( at the green arrow )


Step #2 If you experience chainsuck issues in the biggest cog turn the b-screw clockwise to pull the rear dérailleur back.


Step #3 If you have problems shifting in the smallest cogs turn the b screw counter-clockwise to push the rear dérailleur in.