CoogansBluff

The lever that controls shifting into lower (smaller) gears in the cassette is not working much of the time. Took it to bike shop. They sprayed de-greaser in there, and it seemed to fix it for my next ride, although a few times it didn't work. Then today, before the ride, I noticed it wasn't working, so I degreased again, and got it going. However, it stopped working pretty quickly into the ride, although by the end of a 2-hour ride, it began working again.
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Any advice? Should it be lubed after being cleaned out? Is it just broken?

RiceAWay

If it is Shimano replace it. This normally occurs if you've stored your bike around a clothes dryer but can occur simply from age - once dust gets in the mechanism of a 10 or more speed shifter you cannot get them to work properly again. If it is a Campy a shop should be able to disassemble it and clean the entire mechanism. Just spraying penetrating oil into the mechanism rarely works even for one ride. This is rare in 8 speed shifters

CoogansBluff

I'll have to check to see if Shimano. Most likely yes. It's a Specialized Roubaix. Wonder what caused it. Store it in garage, but no dryer there. I sweat quite a bit, so wonder if that might've caused damage over time.

RiceAWay

I've never seen sweat cause those sorts of problems. The ratchet mechanism in a 10 speed or more has teeth so fine that dust can clog it. If you ride it often normally the shifting keeps it fairly clean. Maybe someone has had luck flushing this out but I never have.

bwilli88 

Shimano will not replace it, How old is it and how often do you shift. Could be a bad cable or just dirty/dusty. If the LBS just degreased it, it could need some lube, a spray grease might help. Not WD-40.

datlas 

Before you pitch it, verify cable is not kinked or fraying inside the shifter, or put new cable in. Sometimes stubbornness to go to smallest cogs is a symptom of cable kinking inside mechanism.

CoogansBluff

It's 2 years old. It worked fine today. LB degreased but also lubed. Then when it began failing, I degreased again without lubing. And now it seems to be working again.

CoogansBluff

Cables have been replaced not long ago, so while that's possible, given its young age, I doubt that it's fraying (yet). When not working, it's not stubborn to go to the smallest cog per se, but rather doesn't shift at all, just kinda whiffs when you shift it. But hopefully problem is solved, or is linked to needing to be cleaned a little more and then lubed, which I probably now need to do after degreasing it again.

BoraxKid

This is obvious Campy fanboy nonsense from a retrogrouch. As OP has already shown, it is entirely possible to clean a Shimano 10-speed shifter that had some debris inside it. Worst case scenario, the shifter might need to be taken off the bike so it can be flushed out more aggressively, but it sounds like OP has already found a path to success with strategically applied degreaser. Good job, OP!

noodle soup

Thanks for saying what I was thinking.

Symox

I sprayed carburetor cleaner in there and it fixed it right up