Defending champion Freddie Spencer was the pre-season favorite to win the championship however, teething problems with Honda's new V4 and early season injuries squelched his hopes to repeat.
Randy Mamola also had three wins to finish second on a factory backed Honda.
Yamaha also claimed the 250 crown with Frenchman Christian Sarron taking the honors ahead of a strong challenge from Real-Rotax mounted Manfred Herweh.
Stefan Dörflinger would be the first ever 80cc champion after the class displacement was increased from 50cc.
[1] The following Grands Prix were scheduled to take place in 1984:[2][3] †† = Saturday race [6][7] Points are awarded to the top ten finishers.