Four stroke

A sissy dirt biker

That must be a four stroke rider because he looks like a sissy.

Four stroke

Engine most commonly used around the world. although on a dirt bike they perform terrible because compared to a 2 stroke, they put out more torque rather than HP and torque is not really needed on a 150 lb machine to get up to speed.

Four stroke rider- hey wanna race

Two stroke rider- sure

Four stroke rider- how come you won, my top speed is higher than yours

Two stroke rider- because I got to a

higher speed faster than you could