Bicycle Mechanics - Braze-On Height Adjustment

Trek 5500 w/full Ultegra - a custom build. Front derailleur appears too high - about 1/2" above chainring and it's at the bottom end of the adjustment. Is there another braze-on mounting/adjustment plate I can purchase that will allow it to go lower or should I let it go? Bike appears to shift properly as-is.

55/Rad

What tooth chainring are you using?

Hey Rev - thanks for the info on the Powerlink...works like a charm.

Different bike, different issue. The crank is a standard 53/39.

55/Rad

Well, hmmm. There are only two braze on Ultegra der. FD-6500 a double and FD6503 for triples. And they travel a little different(The triple drops more when shifting down) but I wouldn't think this would cause your problem. You should be able to get the bottom of the cage with in 2mm of the chainring.
I would go to a Trek dealer and look at a 5500 on the floor, maybe you have the wrong braze on mount.

Bike appears to shift properly as-is.


What's the problem if it's shifting properly? Not trying to be smartass, just wondering why would it needs to be fixed if it's working?

There isn't a problem, I don't think. I just purchased 2 used bikes and went through the process of learning about and changing derailleurs on one of them. The Park tool site was immensely helpful.

Then I took my new found knowledge and looked at the Trek. Although it works fine, the gap is substantial. Being obsessive compulsive, I want it perfect....if it's even possible.

55/Rad

The der can be pretty poorly adjusted and still work OK esp. with a double. But it is oh so crisp if you can get the bottom of the cage1-2mm from the top of the big ring teeth. Less chance of it hopping off to the outside on a bump as well.

After a trip to a Trek dealer to eyeball both the 52 and 5500's, and 30 minutes with a mechanic just shaking his head, I decide to strip the darn thing off the bike. Then I discover.....

The large chainring is a 50!

Did I say I feel stupid? I got the bike used from a good friend for Christmas and all the while I assumed it was a 53. Anyway, problem solved. Good thing too as I was beginning to go crazy.....

55/Rad

Very good. I was wondering myself. That was the only thing it could be (I was thinking) :)