Originally Posted by
topflightpro
As for Hamster's comment, the crank arm bolt should be tightened to torque specs and no more.
Yes. However, in my BB30 crankset, the crank arm bolt has to be tightened to 45-55 N*m (33-40 ft*lb). It is (almost) impossible to reach 45 N*m with a hand-held allen wrench, so overtightening is not really an issue. The OP says that he's "able to remove the non-drive side crank easily", which tells me that the bolt is almost certainly loose.
I would suggest, before you go and buy a bottom bracket tool, to tighten the bolt by hand as far as you can, see if that makes the problem go away, and, if it does, buy a torque wrench and an appropriate socket and tighten it to spec.