A type of motorcycle engine made by Harley-Davidson from 1966 to 1985. The engine is called a Shovelhead because to the "shovel" look of its rocker covers. Though it was manufactured for two decades, shovelheads are prone to leaking oil, over heating, hard starting, vibration, blown head gaskets and other major problems that require constant maintenance. The Shovelhead engine is a pain to take care of, but it has a beautiful sound to Harley fans.
In 1984 Harley-Davidson introduced the "Evolution" motor which required less maintenance, was easier to manufacture and is credited for saving the company from bankruptcy.
Some older bikers who ride shovels hate the Evolution and the later Twin-Cam motors for bringing large amounts of "instant bikers" who would never have ridden a motorcycle or Harley before. But they are just too poor or cheap to buy a new Harley or admit that the Evo is a much better motor.
The 1966 Electra-Glide was the first Harley to have a Shovelhead motor.