Hey all …
I’m having a mystery problem with my road bike and I’d like to solicit opinions from any mechanics, or the mechanically inclined. I am about to take the bike to my 3rd different mechanic, and the first two were unable to diagnose/fix it.
The problem is a combination of lazy shifting, skipping cogs and/or the chain rattling on certain sprockets. My normally excellent LBS, whom I’ve worked with on all my bikes for 8+ years, adjusted it 3 times before I took it elsewhere to get a second opinion. I just picked it up yesterday from the 2nd place, and the problem persists. The symptoms of the problem have been moved up and down the cassette, but they’ve never been eliminated.
Here are the relevant details on the bike:
Bike: Firefly Titanium Disc
Bottom Bracket: Chris King threaded, recently serviced
Groupset: Shimano Dura Ace 9100 2x mechanical, hydraulic
Cassette: SRAM Red 11-32 — brand new, just replaced
Chain: Shimano Dura-Ace 11-speed, less than 200 miles on it
Pulley wheels were recently upgraded to Kogel oversized pulleys; new derailleur hanger was installed due to the original being slightly bent.
The bike was fully tuned-up in March, at which point the BB was fully serviced, the new pulleys, chain and derailleur hanger were installed. From April through mid-June the it shifted great. About 3-4 weeks ago it started to have shifting problems and I took it in for what I thought was going to be a minor derailleur adjustment … however, they couldn’t seem to get it quite right. At this point it was identified that I might need a new cassette after 18k miles on the original cassette (which was also a SRAM Red 11-32). The new cassette was purchased and installed, and while the problem slightly improved, it did not solve it. I took the bike back for them to inspect the cables and housing, which they did … but still not solved. I then took it to a second shop to be worked on and a fresh set of eyes … just picked it up yesterday and I would say it’s worse if anything.
— Has anyone had a mystery shifting problem that couldn’t be easily solved?
— Do derailleurs wear out? (Mine is the original Dura Ace, bike purchased in 2018 and has the same amount of miles on it as the original cassette)
— Should I ask a mechanic to start over with all new cables/housing?
— Anything else I’m not thinking of?
Thanks in advance for any input/insight.
**Also, if any of you are in the Chicago area and have a genius mechanic you might recommend, please feel free to send me a PM. My LBS has a sterling reputation with high-end bikes … but they weren’t able to solve.