Originally Posted by
maddog34
when steel is welded, it gets REALLY HOT... this imparts hardening of the steel to either side of the weld...
butt welding(what we are talking about) makes the weakest type of welded joint of materials...
the area involved sees both tension, and compression loading... tension loaded welds are notorious weak points... the area also sees high side loading, and twisting... this is why it failed.
do the math... almost every stress mentioned will cause a failure... on a frame that doesn't fit the owner... one must also consider the very real possibility of another, as yet unseen, crack, just waiting to show itself... the bike is OLD, and has already cracked, eh?
Time for a duct tape repair?
Sorta just kidding.
Can anyone who has a familiarity with this vintage of Motobecane speak to the incompatibilities regarding trying to move the component set and parts to another frame?
For some reason (unless I get a similar frame) I imagine it's going to be an endlessly frustrating mismatched parts headache.
??