A few years ago I went to the dump and in the metal pile was an old mini bike frame and wheels. I latter figured out it was a 1970 Rupp Sprint. I put a motor and clutch on it and had a little fun. I couldn't help but think how easy it would be to throw a torque converter on it like the bigger Roadster's, Black Widow's and Scramblers. I only would do so as this Sprint was missing so many parts. Especially the infamous chain gaurd that seems to be a million dollars to replace.
So here is a Rupp Sprint mini bike with torque converter. It seems there wasn't to many, (if an) Rupp mini bikes with a torque converter or 2 speed clutchs that didn't have both front and rear brakes. So I found some turbine wheels from a 68, 69 Roadster with front and rear brakes. Missing the brake assemblies I had no choice but to modify the brakes to accept later model brake assemblies. Like all of the big wheeled Rupps from 1970 and up, the Sprint has 1/2" axles instead of 5/8" like all of the other turbine wheeled mini bikes. So I used brake assemblies from 1971 and modified the drums to accommodate the new brakes. I cut off the old drums from the drum hub and welded on a piece of 4" schedule 80 pipe them turned them on a lathe afterwards.
This thing FLYS... It is very fast and will jump right out from under you if you're not careful. I think I'm gonna paint it hot rod black with a little red hear and there and maybe I call it a Rupp Ratster...
So here is a Rupp Sprint mini bike with torque converter. It seems there wasn't to many, (if an) Rupp mini bikes with a torque converter or 2 speed clutchs that didn't have both front and rear brakes. So I found some turbine wheels from a 68, 69 Roadster with front and rear brakes. Missing the brake assemblies I had no choice but to modify the brakes to accept later model brake assemblies. Like all of the big wheeled Rupps from 1970 and up, the Sprint has 1/2" axles instead of 5/8" like all of the other turbine wheeled mini bikes. So I used brake assemblies from 1971 and modified the drums to accommodate the new brakes. I cut off the old drums from the drum hub and welded on a piece of 4" schedule 80 pipe them turned them on a lathe afterwards.
This thing FLYS... It is very fast and will jump right out from under you if you're not careful. I think I'm gonna paint it hot rod black with a little red hear and there and maybe I call it a Rupp Ratster...