I ride a Trek 1200 '04 with a 105 rear derailleur. ive put about 2500 miles on it this summer, i've not gotten in any big crashes, but every 100 miles my rear derailleur's been getting sloppy, and the bike shop's looked at my derailleur. they dont find anything wrong with it, so do any of you guys know what could be wrong? is it just 105's tendency to screw up - i'm getting really annoyed with the derailleur and im wondering if its better to just upgrade to ultegra

I ride a Trek 1200 '04 with a 105 rear derailleur. ive put about 2500 miles on it this summer, i've not gotten in any big crashes, but every 100 miles my rear derailleur's been getting sloppy, and the bike shop's looked at my derailleur. they dont find anything wrong with it, so do any of you guys know what could be wrong? is it just 105's tendency to screw up - i'm getting really annoyed with the derailleur and im wondering if its better to just upgrade to ultegra
I assume you mean sloppy shifting and I doubt if it is the derailleur. Could possibly be a bent derailleur hanger if it's been down on the right side. Much more likely to be cables/housings, etc. - TF

I assume you mean sloppy shifting and I doubt if it is the derailleur. Could possibly be a bent derailleur hanger if it's been down on the right side. Much more likely to be cables/housings, etc. - TF

I second that. I dougt it's the derailleur. At least i would repace that last. More likely worn cable housing or something bedding in. This is were being friends with a good shop
pays off : )