kaimat

So I buy a new bike, works great, no complaints. Then I decide to put a K-edge chain catcher on it using the FD braze-on connection--the FD falls and I don't know how to align it properly.

I bring it to my LBS, the guy spends maybe a minute working on it and says I'm good to go. I go to ride it and it still won't shift into the large chainring, yet he got it into the large chainring just fine.

It's Shimano 105, in theory I know how to shift up but it's not working for me. Even if I push the shifter as far to the right as I can and to where I think I'll break it, it just rubs the chain and the chain doesn't make the jump over.

Someone teach me the proper way to shift it lol. (By the way, the cassette shifts just fine, it's just going to the larger chainring that doesn't work for me.)

vladvm

adjust the cable tension by the cable stops under downtube if you have one.

gadabout007

push harder on the brifter.

The 105 fd is designed to work with both double and triple cranks.

1nterceptor

Go back to the LBS and ask them to show you how they shifted.

WhyFi

Eh? There are double and triple specific FDs in the 5600 and 5700 series. The left 105 lever in the 5600-series was originally double and triple compatible, but that failed miserably and was changed mid-model year.

kaimat

I have a 105 Double shifter and a compact drive train.

Homebrew01

Just because the mechaninc got it to shift on the workstand, doesn't mean it's correct for shifting on the road under load. Take it back, or go to ParkTool.com and learn to do it on your own .... Doing your own work is cheaper & more convenient.

kaimat

Ok, so I adjusted the limit screws on my own and it can now shift up to the large chain ring but it always throws the chain. Is this because the FD is too high or could the limit screw have been turned too much?

WhyFi

With the bike upside down, pull on the exposed FD cable while pushing the pedals around with your other hand. If it shifts up like this, try tightening the cable with the in-line barrel adjustment. If it doesn't, try turning the limit screw CC 1/4 turn at a time.

WhyFi

You probably turned it too much - you should be turning it no more than a 1/4 turn at once. To check the upper limit, shift to the smallest-tooth cog on the cassette and look at the distance between the chain and the FD guide. It should be 1mm or less.

kaimat

It's at a point where it won't go up, won't go up, then when it's adjusted to go up it throws the chain. It's like either it isn't far enough or else it's too much, and it's like 1/8 of a turn difference.

WhyFi

How much space is between the big ring teeth and the guide? If it's more than the thickness of a coin, or so, it's too high.

kaimat

I think I've identified the problem: the FD is crooked lol. The part closest to the front of the bike rubs against it when it shifts up and pushes it off. Should be a simple fix.

kaimat

Nevermind, didn't fix it. Height over large chainring is about the thickness of a penny.

Drew Eckhardt 

The limit screw could be turned too much. If it took that much to get good shifts to the big ring the derailleur may too high, a clamp-on front derailleur may have incorrect rotation, you may have a bent chain ring, or your right crank may not be properly installed.

kaimat

It's a braze-on front derailleur, not a clamp one.

Could I determine a bent chain ring just by looking at it? Anything I could do to tell if it wasn't properly installed?

kaimat

Rofl. Totally fixed now. Braze-on screw just wasn't tight enough so the FD was rotating.