The 800cc MotoGP era in MotoGP was seen as a huge failure for the sport, lasting only a couple of years before the move back to 990cc motors.
It was a decision made to try and slow the bikes down, but only succeeded in making them harder to ride and more prone to highsides.
The positive side of the class was bikes like the Kawasaki 'screamer'. It was never successful in the hands of Ant West and John Hopkins, but that rev ceiling of 20,000rpm was insane. Have a listen and turn those speakers all the way up!