Originally Posted by
3alarmer
...there were a couple of generations of Ofmega cranks and spindles. The later ones used a size and taper that was more or less standard.
+1 this. You can mount an Ofmega crank on an ISO spindle, but it will sit slightly further out than would an ISO crank on that spindle. Take that into account when selecting your spindle length.
Perhaps this might help:
Source: Sutherland's 4th Edition