Front derailleur shim?
 

For those hwo have 32mm clamp on front ders. Where can one get a shim to use them on and steel bike with a 28.6mm seat tube? From what I understand, they need to be like a hard plastic, so they don't move, so a piece of inner tube may work, if you really torque it down, but it just isn't the best to use.

They normally come in the kit (Shimano anyway) if they are compatible. Other than that, I'd guess any old inner tube would do as long as the fixing was secure enough.

You mean like this?

http://www.bikeparts.com/ProductInfo...r-shim885.html

Use the shim that 55/rad found. Plastic or rubber is too soft and flexible.

+1 for using the specifically made product. Never seen them for sale anywhere to be honest, but I don't think using inner tubing would be that drastically wrong. There wouldn't be too much flex if it was torqued up right, I'm fairly confident.

Academic really, seeing as you can buy the actual shim! :D

If it moves a few thousands it will shift differently. Just a derailleur with a stiffer cage will shift faster.

What are you using for a shifter?

Friction shifters will cure a lot of front front shifting ills. Back in my more financially struggling days I set up a triple front derailleur on a Schwinn Twinn tandem using friction tape for a shim. It worked OK.

Any kind of indexing front shifting system can be pretty picky. I'd want to make sure the derailleur was mounted nice and secure. Any amount of slop is likely to cause shifting problems. A seatpost shim that is designed for that exact purpose only costs a few bucks.

This was exactly my situation today. Seems like there aren't many 28.6 mm clamp-on front derailleurs out there anymore (for Campagnolo, anyway).

I can say without doubt, that in the case of a Campagnolo Centaur 10-speed front derailleur sized 32 mm being put on a 28.6 mm steel frame, an old inner tube as a shim simply doesn't work, as you can't tighten it enough.

What does work, however...is a nylon pedal strap! Got any hanging around? Just cut a piece out of it to size, clamp your front derailleur around it, and tighten it until you can't tighten it no more.

A blast from the past, resurrecting a thread from 2005!

Well, I did a search, and this was what I came up with. Don't people on message boards complain about starting new threads without searching through the old ones first?

I used thick card stock to shim a 34.9 FD to 32. It worked great. I was fixing a friend's Costco Motiv MTB that had a bent crappy FD. I gave him an old STX-RC FD but it was 34.9. Anyway in a pinch it worked well... just don't get it wet :)

I bought the clamp for a braze on veloce fd. Works like a charm.

I just buy up all the 28.6 derailleurs I can find. Campy's clamp comes off. It's easy to sway from 34.9 to 28.6 The hard part is finding a 28.6 though.