Thanks, guys. Tony, have a 79 predator on another bike and you're right it hauls arse with single speed and Hilliard clutch. I like my 3-speed hub, though, never had a problem but I don't abuse it - no need. This setup is much faster than the 47 HS that sounded like a lawn mower. I grew up with 2-smokers, so that's what I like. 4 strokes are easier and more reliable, but I like the smell of FAST. How can you tell which version of a Predator you have? I don't know what you mean by a Hemi. Guessing you mean a domed piston. We have strayed dangerous close to motorcycles with these builds, but that's OK with me. (guess that is progress, Dan) I started with a rag mount sprocket, coaster brake only, and no electrics. I like where I am now much better. This bike will smoke my 50cc Sachs 3-speed and my wife's Yamaha Vino. Haven't clocked top speed yet, but that's coming soon. Might mount a Biggs muffler in pipe, it rattles my neighbors' windows, but when it kicks in, I'm gone!