After a drivetrain side low speed collision, the rear derailleur's shifting became less smooth. I suspected the derailleur hanger and pulley cage were bent, so I replaced both. However, after installing the new parts, the rear derailleur continued to shift strangely. To troubleshoot, I reset the limit screw, done micro adjustments, and the high and low end stopper bolts. Eventually, I found a setting where it shifted relatively smoothly in the big chainring, although not perfectly.
The issue arises when shifting into the small chainring with smaller cogs, where there is excessive chain slack. Attempting to adjust the limit screw to increase tension causes problems such as skipping gears or failing to shift from the 10th to the 11th cog while in the big chainring.
Has anyone encountered this issue before? What would be the logical steps to diagnose and resolve the problem?
by noriceno1ife
4 Comments
Is the derailleur installed on the hanger correctly? There should be a little shelf on the hanger and a little nub on the back of the derailleur that rests against that shelf.
That chain looks way too long.
The slack in the chain seems to suggest there might be an issue with the p-tension spring (which could be a result of the cage having been replaced). See [page 36 and up](https://si.shimano.com/en/pdfs/dm/RARD010/DM-RARD010-04-ENG.pdf) in the manual.
B tension screw needs adjusting, and/or your chain is too long. Also, don’t assume that because it’s a new hanger that it’s straight. It still needs aligning with a DAG tool