For saving parts of "display" bikes it would be great--but I don't know I'd have a lot of confidence in vintage forks that got bent way back and then re-straightened by bending them again with that jack-thing.
I never repaired many bicycles though--so if you thought differently, you could claim I don't know what I'm talking about and you'd be mostly right in this case.
Uncle Stretch said:
I always wonder how much you can stress a piece of metal and not have it break later. I know aluminum will bend once and when you bend it back it always cracks. I guess mild steel is a little more forgiving.
Steel can often be straightened safely, if it is not bent much.
Any aluminum parts that get seriously bent are gone, they're DOA and can't be saved. Cut them in half and then take them to the recycling center.
The CPSC has a requirement for fork durability. The forks need to survive getting bent backwards, but they don't test re-straightening them again at all. (-in the USA, the Consumer Product Safety Commission is the federal agency that regulates safety requirements of bicycles-)
A summary of the bicycle requirements can be found here:
http://www.cpsc.gov/BUSINFO/regsumbicycles.pdf
The part on forks starts at the bottom-left of page four (there's only five pages of this outline).
I don't know if the full regulations are available online or not; I've never been able to find them collected as such, and it's not ever been so important that I'd email and bother them.
Also we note: the C.P.S.C. was only begin in 1972. If there were any (US) federal safety requirements for bicycles before that I don't know.
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