Yamaha YZR-M1

Yamaha YZR-M1 (2002–present)

Jorge Lorenzo riding the M1 at the 2010 Aragon Grand Prix
Category	MotoGP
Constructor	Yamaha
Predecessor	Yamaha YZR500
Technical specifications
Chassis	Twin-spar aluminium deltabox frame, multi-adjustable steering geometry, wheelbase, ride height, with aluminium swingarm
Suspension (front)	Fully adjustable Öhlins inverted telescopic forks
Suspension (rear)	Braced aluminium swingarm with single Öhlins shock and rising-rate linkage
Length	2,060 mm (81 in)
Width	650 mm (26 in)
Height	1,150 mm (45 in) measured from identical reference plane
Wheelbase	1,450 mm (57 in)
Engine	Yamaha 1,000 cc (1.0 L; 61.0 cu in) Inline-four engine, 16-valve, DOHC, four valves per cylinder, Crossplane crankshaft, naturally aspirated,
Transmission	6-speed sequential manual cassette type
Weight	157 kg (346 lb) excluding rider 225 kg (496 lb) including rider
Fuel	ENEOS
Lubricants	Yamalube
Tyres	Michelin
Competition history
Notable entrants	Yamaha Motor Racing Yamaha Tech 3 YSP Racing Team Forward Racing
Debut	2002 Japanese Grand Prix
Races Wins 253 101
Constructors' Championships	5

The Yamaha YZR-M1 is a inline-four motorcycle specifically developed by Yamaha Motor Company to race in the current MotoGP series. It succeeded the 500 cc (31 cu in) YZR500 by the 2002 season and was originally developed with a 990 cc (60 cu in) engine. Since then, the YZR-M1 has been continuously developed into several iterations through the 990cc, 800cc and 1000cc eras of Grand Prix Motorcycle Racing.

2002 was the first season which allowed 990 cc 4-strokes to be raced alongside 500 cc 2-strokes. In a change from their V-4 YZR500, Yamaha designed the YZR-M1 (for "Mission One") with an inline-4 engine because it was the format considered to have the best mutual balance with the frame. Also, Yamaha wanted to preserve the superior handling of the YZR500, so the M1's engine was designed to fit in a chassis developed around the basic structure of the YZR500. The M1 was outfitted with an electronic engine management system that controlled the engine braking endemic to 4-strokes. The new engine had 5 valves per cylinder, was fed by carburetors and began with a displacement of 942 cc; in the second half of the season it progressed up to the full 990 cc regulation limit. The frame design also evolved during the season, with adjustment of the engine mounting position and change in the fuel tank shape.

The M1 was test-ridden and developed by Max Biaggi, John Kocinski, Norihiko Fujiwara and Kyoji Namba throughout 2001. It was raced in the 2002 season by Biaggi and Carlos Checa on the factory team, and towards the end of the season M1s were also provided to Norifumi Abe, Olivier Jacque and Shinya Nakano. Biaggi achieved two wins and placed second in the final standings as did Yamaha in the manufacturers' championship.