Klein Frame, Compact Crank OK?
 

I just got a NOS 2003 Klein Q Carbon Team frameset. On the drive side of the seat tube, the tubing is flattened just under where a derailleur clamp goes. I would like to outfit this bike with a 50/34 chain ring combo, but my concern is that this frame is designed for the derailleur clamp to hang relative to a 53. My fear is that I would not be able to clamp safely around the flattened section because the derailleur would sit lower.

I know there is someone out there who can answer this!

On the flat part of the tube should be threads for a braze-on derail. mount so you'll also need a braze-on derail. instead of a clamp. The mount has a slot to adj. for height so you should have no worries.

Nope. Not on a Klein.

OP: There shouldn't be any problems using a compact crank. The little indentation is generally tall enough to accomodate some movement in either direction. A 50t ring is only 3/8" smaller than a 53t, and I reckon there should be plenty of clearance to allow that little bit of movement.

you are the man. thanks