I finally decided on a real plan for the upper shock mount. The frame is a '79 and was originally a dual rear shock bike. I wanted the mono shock look so it took some doing. It's not done yet but it's better.
I slid the cb360 fork tubes up 1 1/2" and then shortened the stem almost another 1 1/2. Eventually I will cut the tubes and re-thread them but for now to keep cost low and get them done I left them sticking up through the upper clamp. This resulted in regular moto bars running right into the tubes. I made my own bars with a bend in the center and just twisted the clamps out a bit so the bars cleared the tubes.
I wanted the moto look for the exhaust but mufflers are pricey! I thought I'd score a mx canister for peanuts on ebay but no dice. Well seeing I don't like mufflers anyway I just made something that looked like a muffler. I am using a stock header and then it goes back to open 1 3/4" pipe. The canister ends I made from 12 and 16 gauge steel and wrapped them in annealed .025" aluminum held down with pop rivets.
The xr75 gas tank is maybe a gallon. The engine gets a solid 60+ MPG so I am hoping to be able to make it between fuel stops but inevitably I will run out. I hate carrying stuff so I wanted the tank easily removable so I can siphon fuel fast and easy right into the tank without the need for a fuel bottle. I am using a Motion Pro fuel line quick disconnect for the line. The tank mount uses a spring loaded quick release locking pin tethered to the tank. The seat and rear fender will use the pins as well so I can have the tank off in 30 seconds or so. This will also allow me access to the carb and coil and wiring fast and easy if need be.
I was concerned at first with the holding power of the pin but it is solid. Some careful lathe work keeps the receiver bungs snug too.