At the time, there was not only the perception that 500ccs was a massive amount of displacement for a two-stroke, but that an engine that size could not be made to run reliably. Well it was a huge amount of displacement indeed, but it turns out the reliability issue was wrong – it just took someone to prove that it could be done.
It was British GP racer Barry Sheene who was was first to really master the 500cc two-stroke, due mainly to the creative design of his race bike. His team, led by famed British frame builder Colin Seeley, took the air cooled 2T engine from a powerful Suzuki TR500 and built a new bike around the potent engine. On this new bike, Sheene quickly proved he could ride big two-stroke just as well as he did the 125s on which he rose to fame.
As good as it was, the TR500 engine was only good for around 80HP at the time. But two-stroke development happened fast once the factories figured out that a race worthy 500cc two-stroke was indeed possible. Yamaha hit back next, using their experience with 250cc 2-cylinders to build a 500cc 4-cylinder bike, on which Giacomo Agostini rode to a world championship in 1975.
But Suzuki was quick to strike back. Encouraged by their success with the TR500, but understanding that they needed a ground-up 500cc two-stroke build, they developed the RG500. The RG500 had a square-four engine developed on the basis of the factory’s 250cc GP bikes, which cranked out over 100 bhp and could reach speeds of up to 175 MPH. The RG500 would become a legend in the skilled hands of Sheene once again, who won World Championships in both 1976 and 1977. Click Here…