5. Prop adapter

The prop adapter is a little different that you can buy from Whackerengines. The main difference is that the front part included 5/16-24 high grade steel screw. The prop must be drilled to 12mm to fit on the hub but the prop nut goes on the hard steel. I didn't like the common solution, where you screw the prop with the bolt using the thread in aluminum. With my solution you can tighten the prop without stripping the thread in aluminum. The back side doesn't need to be so wide, but as I don't have a flywheel I wanted some kind of shield in front of the shaft bearing.

Total prop adapter weight is 1.5 oz