Shimano GRX rear derailleur. 11-34 cassette. 50-34 crankset. I installed the chain following the official instructions: big chainring + biggest cassette sprocket, then added 5 links. After installation I adjusted the B-screw/guide pulley gap, but on the smallest sprocket and smallest chainring the chain is slightly slack. Without any pressure on the pedals it even rests on the front derailleur cage.
The second picture shows the chain on the biggest sprocket and biggest chainring.
Should I remove another link?
Also, when backpedaling while I'm in the smallest 3 gears, the chain climbs up the cassette toward larger sprockets. What can I do to fix this?
by pogoraggie
5 Comments
Chain too long.
Did you set the B-screw gap correctly? From the photo it looks like the cage is touching cassette but I could be wrong.
The derailleur looks a bit close to the cassette, can You adjust it a bit?
Also, did you really only add 5? See how much you can stretch the derailleur on big-big. If you can subtract more than two links, take one out.
The backpedal issue is normal if you’re in the small chainring, it’s a byproduct of crosschaining
Try adjusting your b-limit screw by turning it clockwise. Check your derailleur manual for recommended gap size, but I’m pretty certain you are far under it. This should extend the derailleur and thus take slack out of the chain.