yeah, you've got no worries on that, steel melts at way higher temps than you're ever gonna get in your case, even if you get remotely close to that temp you're aluminum piston would be so melted it would have blown completely outa your exhaust port, and cyntrifical force is only stronger enough to break apart a rim shape like that it there's something attached to it at it's weakest spot, on that crank it's only the mass of that thin slip of metal pulling on it so there's no way it's even gonna bow in the slightest, i'll bet even if you heated that up cherry red and spun it at full rpm it wouldn't even budge