Rupp Roadster 2 questions

Mini Bike & Go-Kart Parts

Greetings everyone,
This is my first post in the forum and I look forward to any help I can get restoring my recently acquired 1971 Rupp Roadster 2. I know these original came with a Tecumseh HS40,but mine has a HS50. Is this engine interchangeable with the original Rupp primary clutch? Any help would greatly be appreciated.
Ryan IMG_4488.JPG IMG_4488.JPG IMG_4491.JPG
The stock 71 Rupp driver requires a 3 inch crank shaft. All the Rupp HS 40's had the 3" shaft. Check the length of your HS 50. If it's 2 1/4" the stock Rupp driver will not work. Black widow motorsports sells a Comet replacement driver that is much better then the stock Rupp unit that will work on either shaft length.
You want to make sure the driver you use is symmetrical. The black widow driver also uses the stock Rupp belt. In the black widow ad above it states you also need the engine shaft spacer. You can use the one from your stock Rupp TC driver, so you would not have to purchase that item as well.
Quite honestly, the stock Rupp set up is not that great. The comet Driver, along with a matching Comet driven unit will run circles around Rupp's factory stuff. And it's much cheaper then finding good used rupp parts:thumbsup:
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