Originally Posted by
Schwinnsta
Sheldon Brown describes a method on his site, using a 2x4 as leverage to do this. I would do a search for it on his site first. At one time I put a Shimano 7 speed on my 1956 Schwinn Wasp coaster brake single speed, but it was not nearly that much increase in space required. My son and I did it just pulling by hand but the stays for a 26" bike make it an easier bend. I have since gone back to the stock set up on that bike.
One method I think might work is take an all thread bolt or rod. First screw on two nuts first put washers on outside of each nut. Then place the rod where the axel was and start cranking to exert outward force. If on each side, the stays have similar geometry and stiffness then they should bend equally. You may have to over compensate because there may be spring back.
Others probably know more about this than me but one consideration is that you are taking the metal beyond its yield stress. If you then decide to reverse this then you again bend it past yield stress and how much this fatigues and weakens the frame could be a consideration. Hopefully others who have done this will weigh in on the matter.
I honestly think this is of minimal concern on something like a Raleigh Twenty. A higher quality steel frame I could see it being a problem.
Aaron
