You could incorporate one of snowys ideas though, if you took the box section that braces the rollers on the lower limbs, and moved it so it was underneath the roller and a tiny bit outside, you could join the opposite end of the roller shaft to a plate attached to the end of the box section, thus supporting your roller rod in double shear. And the box wouldnt restrict it width wise...
Other than that your into changing the steel spec or increase the diameter...
Other than that your into changing the steel spec or increase the diameter...
