ARCHIVE: 1991 was a good year for Yamaha

LUCKY NUMBER SEVEN

1991 was a pretty good year for Yamaha. VJMC’s Steve Cooper remembers how it went down…

As is so often the way in many motor sports, a capricious decision caused a lot of head scratching and work for the Yamaha team ahead of the 1991 season. Michelin’s bean counters decided the cons outweighed the pros and pulled the plug on GP racing tyres causing a swap back to Dunlops. And then latterly the French rubber giant reversed the decision!

Collectively, Yamaha went for the season big time with Marlboro Team Roberts running Wayne Rainey and John Kocinski; Team Roberts Yamaha supporting Kevin Magee; the Castrol Yamaha/Team Roberts looking after Niall Mackenzie and Doug Chandler; Yamaha Sonauto Mobil 1 fielding Jean-Philippe Ruggia and Adrien Morillas; and Ducados Yamaha with Juan Garriga. Other teams had bought into the Yamaha OWC1 engine support system and consequently there were at least 10 more YZR500s out on the tracks at various times. 

New regulations had been introduced at the end of 90 that required all 500cc GP machines to weigh more than 130kg. Yamaha’s factory teams OWD3 implemented an electronic-control suspension which marked the start of the modern hi-tech era in terms of chassis know-how. The factory bikes also utilised an adjustable pivot assembly designed to moderate the forces from varying track surfaces upon the chain tension. By minimising the inputs and negating most of the drive chain backlash, the YZR500’s handling was subtly improved. 

Yamaha had a fight on its hands with Honda’s Mick Doohan really getting into his stride and Kevin Schwantz riding at ten-tenths on the Suzuki RG500. Against this background for 1991 only 13 races counted to the final points as competitors were allowed to drop their two worst scores. And to add to the mix the Yugoslavian round was dropped due to civil war and replaced with a Grand Prix of Europe at Jarama in Spain. Safety concerns saw the Brazilian round dropped in favour of a round at Le Mans, France. 

Out of the top 12 places at the end of the season seven were occupied by Yamahas. Dohan and Schwantz had challenged Wayne Rainey hard throughout the year, but he’d managed to score the firm’s seventh world title for them. The No. 1 rider went on record to state that his bike was the best machine he had ever ridden and likened it to an extension of his hands and feet. With John Kocinski pulling a hugely creditable fourth in his first season on a 500 Yamaha he had enjoyed a grand season. And it was topped off in the All Japan Championships when Paul Goddard won the series title to bring Yamaha its eighth All Japan 500cc class title victory.