Originally Posted by
pinkbeekeeper
I have a 2010 Giant Suede 21 speed bike. I took it in about 2 weeks ago to my LBS for a tune up. I hadn't ridden the bike much at all this year (or honestly last year of no fault of the bike) before taking it in for the tune up. I did notice that when I was going slow and up a hill it did "skip" a bit under pressure in second chain ring and fourth gear only. I hadn't noticed any other issues.
So I get the bike back and wasn't able to take it out for a spin for a few days. When I did to my shock, the chain skipped under normal cadence and in many gears and went into other gears as well. I have 2 other bikes I enjoy riding and havent been very motivated to get it fixed. I am wondering what I should do? Also from reading about the symptoms I at some point may have stretched the chain??? A side question though is why getting a tune up would make this worse?
If the problem is caused by chain stretch (which I suspect it may not be), you can't necessarily blame the mechanic, since it won't manifest except under load, and is hard to see on a workstand.
Chain wear is fairly easy to rule out, by either measuring the chain for stretch (more than 12+1/16" over 24 links that should measure 12") or by using a pointed object to lift the chain out from the chainring at 3 o'clock (the halfway wrapped position). New chains bare lift away at all, and it shouldn't skip unless you can lift it far enough for more than 3/16" daylight between the chain and root of the teeth.
I suspect your issue may be more one of poor RD trim, and if so I agree that the mechanic did a poor job. When you bring it back to correct the problem, make sure he test rides it in front of you, then you test ride in front of him, so you're both on the same page as to whether it's up to par or not.