Necessary to replace crank or just BB?
My left crank is constantly coming loose. It takes a few months, but I think something needs replacing at this point. I started reading into the problem more, and I did not realize that once the crank arm falls off once, it's basically toast? I have an FSA MegaExo + FSA Gossamer Crank. I've actually had the crank arm fall off twice. I only commute with this bike (<2 miles) so I really don't want to go drop $170 on a Shimano R8000. I was hoping to maybe just replace the FSA MegaExo since it'd be a much cheaper replacement, but if the fault lies with the crank then the problem will probably just reoccur a few months from now. I suppose I could just go for a 105 crank since it's a good bit cheaper with marginal weight differences. I was just wanting to get Ultegra everything since I already have Ultegra shifters + derailleurs.