I climbed a parking lot curb once with my 77 CB550F while avoiding a broadside with a car whose driver looked me square in the eye and then pulled out anyway.
Since I didn't transfer all my weight to the foot pegs, the bike bucked me off at the curb and then fell over in the grass and mud. If you're going to drop it, that's a pretty good place, I found out. Pity, *I* dropped on the pavement, ouch. Anyway, I rode the bike home, 7 miles. I staightened or replaced the obviously bent, broken bits. But, the forks didn't seem bent. Sure enough though, a couple months later I noticed the fork seals were leaking. I dismantled the forks and rolled them on the cast iron top of my table saw; flop, flop, flop. Dang these tubes only had 9K miles on them and were wonderful in every other way. I spent some time eyeballing the tubes with occassional glances in the dirrection of my 12 ton hydraulic press. I made some measurement to find the crown peak of the bend in the tube, and located where the tubes were still straight using line of sight and straight edges. Then I made grease pencil marks where the pressures needed to be applied. I made wooden cradles for a fork tube with radial arm saw and a router, as well as a wooden shoe to go on the press ram. I put the tubes in the press fixture, pumped up the pressure and carefully watched the deflection and the springback after pressure release. It was a repetative process, with frequent roll checks and then feeler guage measurements between fork tube and table saw top, until they were straight again. That was about nine years ago, the forks work fine and the seals still don't leak. There were never any kinks in the tubes.
I straightened a set forks from a CB400F a few years later using the same procoess. But, I don't know where that bike is today.
It can be done.
