Hey guys while I was working in the garage tonight I was looking at some pulleys I had and kept thinking what would be a good pulley for my tractor. Well it came to me to us my extra variable speed pulley. Now I know what you are thinking well he is using it for pulling maybe and for high RPM AND HP motors. Well after some testing it seemed to work very well. The pic below show on how to adjust it and how it work. If you screw it in this can be used ti grip the belt tighter and dig into harder surfaces for more traction. Loosen it for softer lighter dirts.

First this is the pulley.

The allen screw that hold the key.

After loosining the screw slightly take the key out.

And as you see there is another half notch so you can turn it a half of a rotation or a full rotation.
And then replce the key.