Here is my thinking on the discussion about cold setting Reynolds 753 and other heat treated tubing:
If the yield stress of the tube can be exceeded by a reasonable amount of bending the tube can be cold set. The question is what do you have then? For heat treated, high strength tubing this cold working causes a proportionally higher degree of work hardening than say 531 for a given net deflection. That can lead to a greater propensity to crack upon later use. My experience with cold setting high strength tubing is very limited. I spread a Tange Prestige rear end from 126 to 130 mm and it was a tough job and required a large deflection of the stays. I was willing to take the risk but I would approach the cold setting of heat treated tubing with big time caution. Of course the real world results are known to those who repair a lot of these and then see the results over time.
Ann Arbor, MI