Broken Campag chainring tooth and chain touching frame

bice Posts: 772
edited October 2018 in Workshop

My drive chain needs serious attention: Campagnolo 10-speed, Italian steel frame.

First, I have a broken tooth on the inner 39T chainring on my double (53T, 39T Campagnolo Record).

Annoying, but easily fixed.

Second, I have built the rear wheel on a brand new Record 10-speed hub for a 1996 Italian steel frame (probably designed for 8-speed).

With a 13-29 cassette this is touching / very very nearly touching the frame.

The chain does indeed touch the frame slightly when reversed. Tension when it is driving forward might just mean it misses most of the time. At any rate, there are no scratch marks that I can see on the frame as yet, and I have ridden this 4-5 times on club rides.


If I had a 12T (as I do, in fact) it would probably clear the frame.

But ... I have a Record triple that I wanted to put on this bike and run with this cassette. There is no way that is going to work nicely with this. The chain will leave the cassette at more of an outward angle and touch the frame badly.

So ... it is back to considering a compact. A Campagnolo Centaur 50T, 34T with modern UltraTorque might work, and I could go for 12T or even 11T, which would lower the chain a few mm and clear the frame. Unless ... the UltraTorque puts the chain further outward of the frame. Then it would touch.

Or, try a square tapered Shimano compact I have on another bike (black, cheap), to see how that goes and stop this guessing with Campagnolo.

Any idea what length spindle I need with a compact on this?