Maybe some of you machinist or engineer guys out there can enlighten me,,
I’ve been tinkering around with a project of putting an XR75 engine in a KX80 chassis. I’ve got the frame and engine mounts worked out pretty descent, and with a little creative intake and exhaust plumbing, I got it going. I’ve ridden it several times, and it seems like this engine/chassis combo works pretty well together.
I used the original XR75 pipe to make the exhaust system. To route the pipe where I needed it to go in the new frame, I cut it into several pieces, then welded the pieces back together in the orientation I needed. This did work, but obviously not a real smooth flowing affair, and it is a bit of an eyesore.
I was thinking, if I had a good way to bend tubing, I could make a nice flowing, contiguous header pipe that goes all the way back to the muffler. Also, I might be able to use tubing slightly bigger than the original XR75 pipe and let it breath a little easier. I’ve been experimenting with one inch electrical conduit, but the benders for that size are pretty limited in the arc of the radius of bend. Obviously, to make a pipe for a bike, it needs to be a fairly tight radius bend to come out of head then make a 180 degree turn to snake to the rear of the bike. The benders I am fiddling with don’t even come close. I also tried spring type benders, but the pipe just ends up kinking. How the heck do they bend tube to those tight radius curves found in bike exhaust headers??