Well I haven't had much time to work on it, but I've made some progress. The hard stuff is done.
Shortened my forks. When I welded the dropouts I guess I used too much heat and it probably caused boogers on the inside.. on both sides, which prevent the fork from compressing fully and get it stuck even with springs in place.
So what I did is I simply shortened the damn fork. I still had about 3" of movement, which is exactly the amount I want anyway. But now at full extension the tire is only about 5" from the bottom crown. Also fabbed up a top brace for the lowers, which is actually a stop for the fork in case it tries to compress more than it should and get stuck (and stop the tire). Hard to see but its behind the lowers in the 2nd pic.
The last couple days I've been making the jackshaft mount. I used the same 4x4 box tubing and will be using the same flange mount 5/8" bearings. I finished cutting out the mount and installed the bearings and a fresh jackshaft, and lined it up to the motor crank. Flat and parallel. Clamped an I-beam level to the crankshaft with the shoulder up against the 4-bolt mount pattern for squareness and went off that. Welded it all together.
Removed some of the gusset material at the head tube, along with the old gas tank mounts that were on the sides. Had to do this to allow my 1gal gas tank to seat all the way down on the tube. Welded in some 5mm bolts to mount my 1gal gas tank on. It is not like the typical kit 1.9l or 2.5L tanks with the studs coming out of the tank, the 1gal tank has much better construction overall, same type gas cap, but the mounts are just flanges with holes similar to the strap that is used for the underside of the top tube. Much, much better design.
Cut out the old front mounts and welded in mine, for the boss on the 212 cylinder that used to hold the pullstart cover, throttle linkage plate assembly, and gas tank I think..
Tomorrow I will install a hinge and shock mount for my seat, and will have to modify the frame under the seat to suit. I have a junk shock off a cheap bicycle but the spring says 750lb/in, which is not going to work unless it is leveraged. I'm gonna put it about a 1/2 the distance from the hinge, between hinge and seat pan spring perches.. but this will still not be enough to even get it to move a tiny bit. I just need a different spring, or a better complete shock.