Originally Posted by
cxwrench
Not very many frames are made from 4130, most are generally higher quality. I think the last one I had was a bmx frame in the late 70's. Cheap dept store bikes might be using it.
I build steel bike frames. I can assure you that almost all of the bottom brackets in quality welded steel bike frames are made from 4130 tube. Dept. store bikes are made from mild steel or Hi-tensile steel.