Rupp Roadster Belt not slipping/help

Mini Bike & Go-Kart Parts

I all most have this rupp running like new. I think today is the first time I figured out how a torque converter works. Some youtube videos. :laugh::laugh: The problem I am having is that the belt is not "slipping" on the back sprocket. The belt kinda gets stuck.:eek:ut: There is plenty of slack in the belt and the torque converter is clean and smooth. All original stuff and never been taken a part. Its all most like I need to put some WD40 in there. Would belt dressing help?:eek:ut: Its hard to push the bike and as soon as you start the engine, "your off":laugh::laugh: Good thing I got the brakes working:thumbsup: Any help would be appreciated. Thanks
The first part of the t-c unit is a big washer that goes on the shaft before the other sheaves it' controls the idle somehow. If it's not that I'm sure. There is a blow up schematic of that rupp at blackwidowmotorsports.


Well-Known Member
I would say its either sticky at the ramp/rear sheave assy, or the driven halves are severely grooved/worn or the belt has an issue or is the wrong one. I would probably disassemble the driven and clean it really well and give it a good inspection if it has not been apart. You could lube the ramp area up pretty good and try to manually work it on the bike I woudl keep any lubricants or belt dressing off the belt and pulley areas though!!

The 1970 I just finished actually slips/squeals just a off throttle, thats with cleaned and gone through driver/driven and the original rupp belt which does not look bad or anything but is 44 years old and probably isn't too happy going back into service after many years of sitting, no sticking though
Thanks Markus. It is the original belt and looks pretty good. Like you said, after 40+ years, I'm sure its not happy. :laugh: Everything is in great condition. The bike actually has low hours because it always ran like a POS.:laugh: Somebody may have mentioned to me that there is no adjustment on the motor:doah::laugh:. I might of got the engine to go back 1/8 of a inch. I'm going to try it again before I take it a part. This bike is like a 42 year old headache:laugh: