I'm in the middle of building a Soma Double Cross Disc and am using components from a Trek Portland, (forks on the Trek went bad, and I missed the feel of a steel frame) I have Bontrager Select Disc wheels, and when I put the wheel in the front fork, there is a millimeter or less clearance between the rotor and the fork. (I have not installed the brakes (Avid BB7)). Is that normal?
On the Trek the distance between the drop outs was smaller, but the distance between the forks at the place where the rotor was, was greater.
I'd feel more comfortable with couple more mm of clearance. Is there a way to increase the effective length of the front hub so the forks are farther apart when the wheel is locked in place? Or should I not worry about it?