Originally Posted by
Anonymous238
I'm tightening these parts as damn hard as I can and I can bench 200+ easily. What gives?
I think that is your problem... Tightening too hard. That is the only thing that makes sense. Crank material (typically aluminum) is always softer than a pedal spindle (hardened steel), way softer, different league.. If one or the other is going to strip, stretch, or somehow get damaged from improper installation, it will be the crank. It depends on your specific cranks and pedals but ~ 30-40NM (25 ft/lbs) is a good start. A crank arm to BB pinch bolt torque varies but I believe Shimano Hollowtech are like 10 NM. Non pinch types (square/spline) are usually in the 30-40 range. Not much at all. If you are cranking any of these down, the crank will fail. Same applies to your seat, stem, handlebars and any other bolt.