I'm having troubling installing a brand new CX1 GXP crank. The bottom bracket bearings, also new, feel like they start to bind as soon as I tighten the crank bolt enough to remove the last bit of play. Torque spec for the crank bolt is 425-478 lbs. I'm getting the bolt nowhere near that snug, barely beyond hand tight. The BB shell is 68 and has been faced. I installed the GXP bb with 2 spacers as per instructions, no prob. It seems like the interface between the cranks and bb cups is not right. The instructions are straight forward: Install the bb w/ or w/out spacers (68 or 73 shell), slide in the drive side crank, put the grooved bb cap on the crank spline, then attach the left arm.

Just for grins, after going over the 5 steps in the instructions and repeating them a few times, I put a crush washer on the drive side crank and reattached everything. The crush washer helped in that I can now tighten the crank bolt a bit more before the bb bearings starts to feel pressured. I still can't tighten the bolt enough to feel good about it and certainly nowhere near spec'd torque. The crank turns smooth by hand, but it takes a bit of effort to turn. When I stop turning, the crank stops moving.

For more grins (and a sanity check) I installed an FSA bb and crank on the same bike and it spins free and smooth with no play.

WTF? Any ideas?

Thanks,
Steve

A GXP crank works by clamping the non-drive side bearing between the spindle and arm. The crank really can't move after it's tightened so other than setting chainline with the non-drive side spacer, other spacers don't really matter.
Try replacing one of the drive side spacers with a thinner one or removing entirely and see if it helps.

I believe the CX1 is made to fit road frames with a 68mm bottom bracket, so it does not use any spacers with a GXP bottom bracket. The instructions with the bottom bracket are for installing an MTB crankset, which has a longer spindle and needs the two spacers if it is installed in a 68mm bottom bracket. To be clear, road spec cranksets don't use any spacers with a GXP bottom bracket.

Solved! I removed both spacers and left the crush washer on the drive side. Good torque, good spin, no play. Thanks for your help!

Cheers,
Steve