The Yamaha YZF-R1, or R1, is an open class sport bike, or superbike, motorcycle manufactured by Yamaha Motor Company since 1998.

Yamaha launched the YZF-R1 after redesigning the Genesis engine to create a more compact engine by raising the gearbox input shaft and allowing the gearbox output shaft to be placed beneath it. This design feature was revolutionary, called a ‘stacked gearbox’, it has set a precedent for other manufacturers to follow. This “compacting” of the engine made the total engine length much shorter overall, thereby, allowing the wheelbase of the motorcycle to be shortened significantly. This, in turn, allowed the frame design to place the weight of the engine in the frame to aid handling because of an optimized center of gravity. The swingarm was able to be made longer without compromising the overall wheelbase, which was a short 1385mm. These features, combined with a steep fork angle, exceptional brakes and racing streamlining, created a bike that was unbeatable on the race track at the time. Four Kehin CV carburetors of 40mm diameter fed fuel to the engine, 140 bhp was claimed by the factory, at the countershaft. USD 41mm front forks supplied by KYB mounted 300mm semi-floating disk brakes. The instrument panel was revolutionary, having an electrical problem, self diagnosis system inbuilt, and digital speed readout. The exhaust system utilised an EXUP valve, which controlled the exhaust gas flow, to maximise engine power production at all revs, creating a high powered but also torquey engine. The twin headlights were powerful, allowing high speed travelling at night. The bike had a compression ratio of 11.8:1 with a six-speed transmission and multi-plate clutch.

The 1999 R1 saw only minor changes, apart from paint and graphics. Notable improvements were a redesigned gear change linkage and the gear change shaft length being increased. Fuel tank reserve capacity was reduced from 5.5 to 4.0 litres (1.2 to 0.9 imp gal or 1.5 to 1.1 US gal), while the total fuel tank capacity was unchanged at 18 l (4.0 imp gal; 4.8 US gal).

Motorcycle Consumer News tests of the 1998 model year YZF-R1 yielded a 0 to 60 mph (0 to 97 km/h) time of 2.96 seconds and 0 to 100 mph (0 to 161 km/h) of 5.93 seconds, a 1⁄4-mile (400 m) time of 10.19 seconds at 131.40 mph (211.47 km/h), and a top speed of 168 mph (270 km/h), with deceleration from 60 to 0 mph (97 to 0 km/h) of 113.9 ft (34.7 m). For the 1999 model year, Cycle World tests found a 0 to 60 mph time of 3.0 seconds, 1⁄4-mile time of 10.31 seconds at 139.55 mph (224.58 km/h), and a top speed of 170 mph (270 km/h).