Is my chainwheel warped?

[boydj]

BB30 has the axle on the crank, similar to external bearings, but has the bearings pressed into the bb shell.

 

[autolycus]

Thanks - i think i understand the difference between the two types now. Mine is clearly a GXP.

 

[autolycus]

Swapped the BB and the dreaded croak has gone - thanks for all the advice suggesting this solution. I also took a couple of millimeters off the captive screw that holds the cable guides underneath the shell - i'm sure that was what caused the gouging on the old bracket. Finally i dismantled and rebuilt the chainset, but could see nothing obviously wrong there. I still can't find a spot on the h screw that gives me clearance all the way around the outside and inside, as described in my OP so, it looks like there is some warping. But if i adjust it so that the outside of the chain rubs slightly in places in top gear and the inside of the chainwheel entirely misses the cage, i don't detect a noise when cycling. Perhaps i should leave it at that?