Machining a Pully

[Steve Hartig]

So, I'm re-vamping a go cart that we pulled out of the weeds at my friend's house.

The original setup had a 433cc snowmobile engine with a variable pulley attached by 1-1/4" wide v-belt to a 4 wheeler rear end.  The rear end also has a variable pulley on it.  We're selling the engine to get some money for the project and we'll be replacing it with one from a pressure washer.  I understand that it'll be quite a downgrade, but we don't wanna fuss with getting the snowmobile engine running.  Anyway, the idea is that there will be a static pulley on the engine's crankshaft (welded to a centrifugal clutch) with a tensioner putting pressure on the belt as the driven pulley changes size, to keep everything tight.  Does this seem like a good idea? How should I determine how big I want to make the pulley? 

-Steve

[Jim Rawson]

Out of my league, but this may help.

http://www.culvermotor.com/Engineering-Formulas/Pulley-and-RPM-Calculator.html 

[Mrspeed700]

clutch should all ways be on engine. Check out Northern tool they have a go cart section. 5hp is capable of 30mph with less than 100lbs and proper gearing.
Rich