I'm having problems with my chain rubbing on my wide 2.4" Panaracer FR tire, currently using a 116mm 68/73 BB on a 68mm Foes FXR shell. If I put both 2.5mm spacers (needed to use the 73mm BB on a 68mm shell) on the drive side, it gets me much improved chain clearance and doesn't cause any trouble on the other side. Using both spacers on the drive side means the BB threads only go about 3/8" into the shell on that side though. Is that okay? I'm not worried about the threads pulling out, just wondering if that puts too much load on too little shell on that side. Don't want to ovalize the shell, if that's possible. I could go to a 118.5mm BB, but that will only get me another 1.25mm per side.