These are tiny engines from a company called Rotamax. They come in the two sizes seen here, a 650 cc and a 1300cc. Rotary engines (think Mazda's RX series) are light and powerful, but suffered from emissions problems in the past.
This would make a cool custom motorcycle, just add a Harley-style 6 speed transmission and you'd be in business. I don't know about the turbo add-on, though, the rotors are air cooled so adding forced induction might just be too much.
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