sadlebred & other cyclists

kat.in.the.hat

have you heard of anyone having issues with the shimano 105s and a double chainring?  I can't get the %)*&#*)!( thing to upshift and it's driving the hubs and I bonkers.

JW28

Nope, there shouldn't be a problem with those parts even if you've got a triple derailleur. You probably just need to adjust your front derailleur (possibly the limit screws). If you don't know how to do this, either google the instructions (pictures and/or video help, I'm no good at describing it) or take it to a shop.

Sadlebred

1. The front derailleur is not adjusted properly. It's a pretty simple adjustment. You can find directions on www.shimano.com or probably Youtube. The directions are universal for Shimano front derailleurs. (Uh, my local shop does all my mechanical work.)

2. The cable broke inside the shifter. It happens. I'd let a shop look at it and replace the cable and housing. It should be less than $20 or a bit more if they have to spend time getting the cable out of the shifter b/c sometimes it will get stuck in there.

3. Is the front derailleur moving at all? (If not see #2). The derailleur itself could be hosed and need to be replaced.

4. If the chainrings are really worn, the "ramps" on the teeth could be causing the problem. Typically, this will only cause a mis-shift and not cause it to not shift at all.

I'd drop it by your local shop. Chances are it's something pretty easy to fix. 

HTH! 

LesPaul

I had an issue with the front derailleur not shifting into the big ring.  Turns out a screw had fallen out and it was out of place enough to prevent shifting.  Easy fix.

kat.in.the.hat

We've played with the tension until it can't be adjusted anymore, looser, tighter, etc.

It will shift on the work stand but won't shift when it's outside or on the trainer, so basically, anytime you put weight on it.  Just frickin annoying.