This guy could could ride a flat track pretty good but is better known
for sliding around asphalt tracks. He didn't win this race but the
next day he went two miles down the road and won the AMA National at
Talladega. Kenny Roberts, sometimes known as the King.
Roberts left his mark on Grand Prix motorcycle racing as a world
championship winning rider, an advocate for increased safety standards
in racing, and as a racing team owner and a motorcycle engine and chassis constructor. His dirt track-based riding style changed the way Grand Prix motorcycles were ridden.
Source: Here