Early in the history of motorcycling, everything was four-stroke. Four-stroke engines crashed the party in the late '90s, rose to prominence in the mid-2000s and have remained in professional ...
4stroke is used in gixxer.2 stroke engines are no longer used in any bike as it causes more pollution and are not efficient as 4 stroke engines.
Although they still exist, 2-stroke diesel engines aren't all that common, and 4-stroke engines are what you'll commonly see ...