There is a historic model, the Clymer-Muench "Mammoth" motorbike where an enthusiastic mechanic genius built a motorbike around a 4-cylinder engine from a small car in 1966. Then the biggest and baddest motorbike, they were successful, but not financially so. They tried the same thing in 2000 with building 15 copies of a new model using a turbocharged 2 litre car engine putting out 260 horsepower...
MÜNCH
Seems they are now building electric motorbikes, but have not heard of commercial success.