Originally Posted by BarelyAWake
I'm sorry man, but I feel I gotta point out that ya really shouldn't "squeeze" or crimp any tubing you're depending on for structural integrity regardless of it's material - for exactly the same reasons stated for aluminum.
In my option is it depends on the thickness of the tube material and how far you have you have to squeeze it.
Take this old Moon Dog I started motorizing today.
The back tube was perfect size, but the front tube as just a 1/4" too wide to let the front studs by.
On something like a Cranbrook you can just squeeze it with channel locks, but not this heavy steel Moon Dog, I had to break out the heavy duty C-clamp
That clamp is as old as I am, it was my dads, and that black on it is roofing 'hot tar' from decades ago when I did roofing
All it took was a couple of turns at the fattest spot to tweak it in at a little spot for the studs.
As you can see I didn't squeeze it all the way in for the rounded mounting brackets to fit over too, just enough for the studs to squeeze by.
This had the added benefit of just enough room on the bottom bracket to leave the shifter cable where it was, and with studs snug against the frame, that right stud will counteract the motor torque well too.
In short that motor is mounted in solid and I just can't see that compromising the frame integrity in any way, and certainly better than a single stud through a drilled hole in the middle.
That way provides no lateral support at all.