Originally Posted by
mconlonx
Crank falling off is an assembly issue on the part of the shop. The "cotter" the shop could be talking about is the safety tab in the slot at the end of the crank arm which should key into a matching hole on the crank spindle/axle. Sounds like they did not torque down the two bolts at the end of the crank.
Yeah I was thinking safety tab too - essentially it just makes sure the left arm is on correctly before you tighten down the clamp bolts. But "cotter pin"??? What kind of mechanic would use that term to describe anything on a modern crank? And the clamp bolts should be checked after a shakedown period but if the arm came loose he could've damaged the whole crank. This is scary bad.