Shimano Shift Problems
 

I was hoping someone here could help me. I am having rear shifting problems with a Shimano 105 setup.

Everything shifts great until I go from the largest cog in the rear to the next smallest cog. When I shift I hear one click, but the chain moves down 2 cogs. I am not crosschaining, the chain is in the small ring, although same thing will happen on the big ring. The chain and cassette are new, new cables and housings, and had the derailer hanger alignment checked and adjusted by LBS.

When I put the bike on the stand and shift while turning the cranks slowly, it seems like the shifter is letting out too much cable causing the chain to skip to the next smallest cog.


Bike otherwise shifts great. I am stumped.

Is it possible the shifter is starting to wear out after 20000 miles?

Any help would be appreciated.

I expect your low limit screw is set slightly too tight so the chain isn't really shifting to the largest cog securely. Try loosening it 1/4 turn at a time and see if that corrects the problem After each adjustment, check carefully to be sure it doesn't let the chain spill to the inside.

Thanks Hill, i will check that.

+1 Hillrider.

If you examine the innards of an indexed DT lever, you can see there's a bigger jump in cable travel to the smallest cog. AFAIK it's fairly typical for there to also be a slightly increased pull to get on the biggest cog too.