What is the typical rear spacing for a cross bike? I figured it would be 130mm, because most crossers use Road stuff, but the Salsa las cruses frame is 135. What gives?

I think 130mm is the standard, but some brands (the MTB brands?) use 135mm. Surly offers a steel frame with 132,5 spacing, that fits both 130 and 135 (bending the steel 2,5mm isn't too difficult).

That sucks. Heres my dillema. I'm building a cross bike on the cheap (long story as to why) and its gonna be a single speed. What I'm gonna do is build a flip flop rear wheel that can be transferred to my fixed gear if i ever decide to go geared for cross. The fixie is 130, the salsa is 135. is there anyway I can just put a spacer on each side rather than having to buy a new axle and space it out? Also, I'm getting Pauls fixie hubs.

The standard is 130mm, but before the genuses (genuii?) at the UCI banned discs many maufactures were moving to 135mm (try finding a 130mm disc hub). This ment many left them at 135, some never got there and some may have gone back.

With the fixxie it is easy, just have a spere 5mm spacer that can slide/screw on the LHS and there should still be enough axle for the nut.

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