Yamaha YZR 500  1990 - 1999

The Yamaha raced the YZR 500 since 1973 - for 30 years over 28 generations. Till 2002 20 different riders won 115 races for Yamaha, and also won 11 world championships and 9 constructor's championships with the YZR.

The Yamaha YZR500 machines from the period 1990-1999

The 1990 Yamaha 0WC1 had an upside-down front fork and power was increased to 155 ps. Wayne Rainey won 7 races with it and scored his first World Championship. Yamaha again won the Manufacturers World Championship, now for the 6th time. The 0WC1 motor was also later the basis engine which Yamaha made available for customers, as in the ROC bikes.

From 1991 onwards minimum weight for 500 cc GP racers was 130 kg so Yamaha concentrated for the 0WD3 on a new suspension system. This was designed together with Ohlins and called “CES”. It was an electric system with sensors measuring the suspension stroke, which was “translated” and fed-back to the suspension. The rider could adjust the system as well from the handlebars. Wayne Rainey won 6 GP’s with the 155 hp 0WD3 and his second World Championship. John Kocinski also won a GP, therefore Yamaha had another Manufacturers title as well. And Peter Goddard won the Japanese Championship, so it was a good year for Yamaha!

The Yamaha 0WE0 for 1992 was Wayne Rainey’s tool for his third World Championship. John Kocinski also won a GP and became 3^rd finally. The 0WE0 had 160 hp now and later in the season the engineers changed the ignition sequence for a smoother power delivery and better acceleration.

Yamaha’s engineers found a few more ps for the 1993 Yamaha 0WF2, it now had 165 hp. It needed a new frame for the larger lateral forces. But Wayne Rainey used the 0WF2 only for the first 9 races, thereafter he swapped the frame for a ROC one.

Luca Cadalora was successful with the 1994 Yamaha 0WF9. It brought him the 2nd place in the World Championship that year. The frame was again new and the engine had even more power. Norick Abe also had his first GP ride on this bike. The 1995 version had a “Ram-air” system forcing cold air to the carburettors.

In the 1996 Yamaha 0WJ1 the bore/stroke was changed again back to the previously used 54 x 54 mm. It gave under the new conditions a better spread of power through the rev-range. Yamaha also used a new material for the pistons and the frame design was modernized in not using a sub-frame for the seat anymore. Norick Abe scored his first GP win on the 0WJ1 and also Loris Capirossi won a GP.

The Yamaha 0WH0 for 1997 had a new engine with an enlarged engineangle of 75 degrees. This was also done to create more space for the large air-box needed. The shape of the exhaust ports was changed into a kind of “T” shape. The motor had new crankshafts and the drive axle of the gearbox was mounted higher in the crankcases. Luca Cadalora won 2 GP’s with it and finished 6th in the World Championship, Norick Abe became 7th.

In 1998 the bikes were run for the first time on unleaded fuel. The Yamaha 0WK1 had therefore a different compression ratio, a new exhaust system and the Mikuni carburettors were exchanged for Keihin ones. The bike had good power as Yamaha had also reduced the internal friction and improved the cooling system of the bike. Remarkable was that the cylinder angle was decreased again back to 65 degrees! Norick Abe, Jean-Michel Bayle, Regis Laconi and Simon Crafar were the riders in 1998. Max Biaggi and Carlos Checa came into the team for 1999. Both Biaggi, Abe and Laconi won a single GP in 1999.
 

1991

1992

1994

1997