I turned two steel posts that are welded to the plate on the end of the bar, then slipped polycarbonate pieces turned to shape over those. Poly pieces have a slot milled in them to fit over the plate, etc.
The rim fixture I made using the same 1 1/2" square tubing. Found the 4" diameter nylon round stock at McMasterCarr. Milled undercuts to hold the edge of the rim. One has a cam milled into it so you can tighten the rim against the other two stationary blocks. I haven't yet drilled additional holes in the frame to accommodate rim sizes other than 17" that sportbikes use. I'd have to make the undercuts larger if I wanted use it for the CB steel rims.
To remove old tires (on the ducati) I break the beads, then use a hunting knife to cut around the sidewalls. A bead of Dawn dish washing soap around the sidewall where you plan run the knife makes that part really easy. Then the remaining bead & portion of the sidewall can be pulled off by hand. I'm happy to report that there's NO paint marks after putting 5 or 6 tires on my Hypermotard.
