the stock 5" system is just bad and you can't get parts, or even a belt. if you want to ride this bike, you need to update it to the 6" comet (clone). i have a hell of a time getting original jackshaft/driven units off speedways. most of the time i end up just cutting them off unfortunately. but i will say in the few times i have gotten the originals off, i have saved them... and traded them to Lam for other parts! ha! but seriously who wants parts for system that you can't buy a new belt? and a system that really barely works anyway.
The belt situation is the major buzz kill. i guess you could change to a 6" comet driven and use the original speedway drive. but then you have to modify the comet to use a 5/8" belt. with a 6" driven you can get a Cat99 (5/8") belt. but to me not worth it, so i got comet for the drive and driven with a 3/4" belt.
I hear and appreciate what you're saying. Here's a few questions:
1. The very nice and informational pinterest repair page says you need to do some cutting on the engine mount plate to account for the move to a 6" - is that true, because, if so, then that's a permanent change.
2. Also, it looks like the bearings are secured with a set screw, or is that a pin that needs to be drilled out?
3. I assume the nice chrome cover still fits over the comet pulley on the engine shaft?
4. One other question - I have the 6" set up that Speedway went to on their pricier models - a whole thing with the jackshaft, the bearings, everything, so I do have a ready to go 6" driven system I can use.