Hi Ron, I just got back from a ride on the little one-(fabulous Jan. thaw with 65 degrees) it power peaks right at 5 grand, mounted on an old Huffy mountain bike that I stretched 3 inches. With gastank and muffler removed, it sits up in the frame.
I put the gastank on the top tube covered with a camera bag (like a motorcycle "Tank bag"). The bike looks like nothing one would want to steal- engine is covered with bags too.
I am using a sturmy archer 3 speed as a jack shaft, the bike goes just over 30 (depending on the weather- goes faster in the cold).
I was looking at the tach and not much at the speedo- second gear will rev out to 5 thousand - maybe 25-27 mph and high gear flattens the motor out rev-wise but goes a little bit faster.
Most of the time I am crurising at around 20 with a very relaxed engine speed. That is bike one.
Both bike one and two need to be registered (NY) and need lights, so I use 24 volt scooter motors driven off a pulley (half speed of the engine) to drive lights. Both bikes have the engine mounted on a plate welded to an added cross bar. Both use belt primary drive with idler and HT type handlebar lever.
Bike 2 uses the 212 and single speed drive (not sure of the ratio), moped wheels, full suspension stretched bike frame.
What I don't like about this is I can't pedal with the bike beyond 10 mph- no multiple gear-set like the bike one. But it rides and handles like a small motorcycle- nice.
Currently, am using cruiser bike chain on the engine final drive, but because of clutch slippage (really need a bigger engine pulley for more wrap around)- I have not shredded the drive chain. Probably would brake it if the clutch would bite hard.
Other guys mounted the 212 on an angle onto the seat-post tube and used a cvt - works real well, but I do not know wether the vibe issue is any better mounted that way.
The cvt is a couple of hundred bucks and would surely turn the bike into a small rocket.
To control vibration, I use "Isolators" from Mc Master Carr. they are cylindrical rubber deals with bonded in studs. I placed one each instead of the normal engine mount bolts, and one on each side of the top (to control engine twist).
These work very well. Fortunately, I had allowed just enough room to the top tube of the frame to raise the engine with them.
The 212 actually makes about 9.5 hp @4400 rpm when the exhaust is opened up and the aircleaner off (actually the stock air cleaner may not restrict it but the dyno test done by a member of Bob's 4 cycle gokart forum had done the test minus the aircleaner).
I run a real long exhaust system with a gutted moped muff and re-jeted carb. On a 120 pound bike you feel some power.
I took some pics, but this computer is a puzzle to me- tomorrow I will try to post some on the other computer.