IDK.......it's not to difficult to gear a 212cc HF Pred to go 70+ mph. I've had mine up to 65mph on flat ground recently. Ya really think ya wanna go 70mph on a bicycle? 65mph is plenty fast......on a bicycle!i want a 70MPH bike though and its one of the best ways i have found
The drawings in the owners manual available at the link you provided sure do look like the Greyhound 79cc from a couple years back... The only difference I see immediately would be the engine mounting; the new engine uses the Predator style mounting adapter plate whereas the Greyhound you bolt directly into the bottom of the engine.just got my 79cc pred. it looks really nice. so dont be scared to order from the HF link. http://www.harborfreight.com/79-cc-ohv-horizontal-shaft-gas-engine-69733.html
Yes, for real.....it looks something like this:for real what kind of a CVT or jackshaft and gearing do you use?