Originally Posted by
Inpd
No, he thinks it is hi-tensile steel which is not as strong as 4130 CrMo. That is absolutely incorrect. The rear triangle is 4130 steel.
Just so it is clear, 520 is a tube model, not a steel alloy. The 520 tubes are made from 4130 CrMo steel or at least an alloy so close that it isn't any use to argue about it.