I have a PR6 question for you: does the steerer tube come pre-trimmed or does a bit of it extend beyond the stem? I only ask as I'm contemplating buying a PR6 to build up with my MORF aerobar (when Frank finally ships it to me) and a bit of exposed steerer would ease my BTA concerns.

Also, what's the maximum tire clearance (measured width) for the PR6 disc?