Hi Tom and welcome to the forums...I understand both @redneckracing674 as well as @GW's Motorized when they mention the cost factor, at least for them, as they are still in their teens and do not have a whole heck of a lot of bucks to play with like us old farts...(I am only 4 years younger than you are)...lol...I would even have to try and save up for more expensive Items because I am not getting any richer in my retirement on my monthly Social Security deposits...lol...lol.
I really liked seeing your URL link for the Sportsman cetrifugal though as it does have more bang for the buck and would prove more rugged and reliable than the cheaply made alternatives that are available on the market at the moment...lol.
Ps...They may only be teenagers but they are pretty sharp when it comes to building things like these bikes and know how to adapt things when something isn't an exact fit...Like mostly anything we have to build with that is...lol...They have some pretty good skills and abilities going for them.
Not a boardy Damien, it's a Sportsman Flyer 80 set up for the road.
Currently I am macking a custom engine mount to vertically position a 79cc Predi onto the frame of a huffy, and junking out all the BB junk.