[bosax]

Well, I have this new frame. The only problem is that the driveside crankarm (and only driveside) rubs the chainstay. I've tried with both Shimano and FSA external BB compact cranksets and the problem can be fixed with a 3mm spacer. While the non-drive side crankarm will tighten down, I'd feel safer if the axle were a little longer. Of course I could fix the problem with a MTB crankset, but I don't want to have to buy a new crank and then rings. So my questions are thus:

1. What compact crankset has the longest axle (assuming cups are the same)?
2. Which compact has the largest Q-Factor?
3. Can I put a 50-34 on a 104BCD and where would I get the rings?
4. What can I do besides returning the frame?

Thanks

 

[C-40]

chainline...

What you need is the correct chainline. The tip of a tooth on the big ring should be 47-48mm from the center of the seat tube. Measure from the side and add 1/2 the ST diameter.

If the little ring rubs, then the frame is not made properly and it should be returned, if it requires the chainline to be off by 3mm.

 

[MR_GRUMPY]

How about some additional info on the frame?

 

[bosax]

The rings are fine, no rubbing. It is the crankarm by the pedal that rubs and only only on the drive side. I thought that maybe may crankarms were bent, but it is that way with all the extra cranks I have. The frame is a new cyclocross frame that doesn't have curved stays and will take any 29er tyre that you have.

 

[C-40]

oh...

I misread, but the answer is still the same. There's no excuse for a frame to be built with crankarm and chainstay interference unless is was made to be used with an MTB crank.