>>1069740>muh fatigue limitExcept that pretty much any steel frame that's not made out of heavy gaspipe *certainly* has areas that are stressed above the fatigue limit. Ask any framebuilder or shop monkey and they'll gladly talk to you at length about all of the cracked steel frames they've seen.
Meanwhile, yeah, aluminum has no fatigue limit, but with the stress levels seen on bike frames, fatigue isn't particularly any more of a concern than it is with steel.
https://www.sheldonbrown.com/rinard/frame_fatigue_test.htmIf you're so freaked out by aluminum's lack of a fatigue limit, why are you riding on aluminum handlebars, stems, seatposts, cranksets, etc. All of those will fucking ruin your day if they fail suddenly, yet I only ever hear hand wringing about aluminum from armchair engineers when it's discussed as a frame material.
t. actual mechanical engineer
