|The 1977 500cc CanAm street bike never made
it into production. Only 2 or 3 prototypes were ever built (circa 1975). One
was a street version which produced about 60 horsepower, while the other was an 85
horsepower road racing version. The engine was borrowed from a Bombardier snowmobile
and modified to accept a 5-speed gearbox. The powerplant was liquid cooled and
utilized a single horizontal rotary valve. The exhaust system was unique. The
lower pipe on each side was an expansion chamber, and was connected to the top pipe
(mufflers) with a small tube. This allowed expansion chamber performance while
remaining quiet enough for street use. This machine never went into production
because proposed EPA emission standards threatened its marketability in the United States.
Tony Murphy wrote a magazine article about this motorcycle in 1976. He recently
informed me that the prototypes are still running strong somewhere in Canada.