The changes to the new R1's intake and exhaust systems have raised the engine speed at which the peak output of 152 horsepower is produced to 10,500rpm and these technical improvements have also enhanced the new bike's over-rev characteristics for stronger performance after peak rpm has been exceeded.

To match the higher engine speeds the 2002 model is equipped with new alloy cylinder liners with a higher silicon content that ensure reduced heat distortion for consistently high performance and reduced oil consumption, and new piston rings are also used in association with the new liner material.

Another change that has been made to match the engine's higher operating speeds is the use of carburised connecting rods with redesigned fastening bolts that offer a 10% increase in axial strength for increased high-rpm durability. Also new for 2002 are uprated exhaust valves that weigh 2g less that the 2001 valves for more instantaneous response at high rpm.

Manufactured from titanium, the new-shape header pipes weigh 1kg less, and the revised 4-into-2-into-1 layout (2001 model was 4-into-1) is designed to boost the engine's low to mid-range torque and also improve high-rpm power characteristics.

The ECU activates a solenoid that opens the air cut-off valve. Air is then fed directly from the air box into the exhaust ports to optimise the re-burning of exhaust gases. Yamaha's famous EXUP system has been made even smaller and is also 500g lighter for 2002, and this 2-shaft new-design exhaust ultimate powervalve features two butterfly valves, one of them operating in exhausts 1 and 4, the other operating in exhausts 2 and 3 to give more accurate and efficient operation together with stronger torque characteristics.

The new EXUP motor has been repositioned on the lower right side of the collector box close to the valves, and this has enabled the use of new low-friction EXUP operating cables.

The second-generation R1's higher revving engine is equipped with an uprated cooling system featuring a radiator with a new ring fan producing 20% more air flow. To ensure consistent engine performance over a wider rpm range, the R1 is fitted with a larger oil cooler that achieves 20% better cooling performance. Total engine oil capacity is increased by 200cc to 3.8 litres, and to handle this higher volume the shape of the oil pan is revised and a larger oil level inspection portal is used.

The new R1 is equipped with a redesigned gearchange pedal and rod for reduced effort when shifting, and the 6-speed transmission's shift cam has been treated to a tin shot peening process that gives an extremely smooth surface finish for slicker gearshifting.

Operated by lightweight and compact direct ignition coils, the new iridium spark plugs produce a powerful and reliable spark, and perform efficiently in the wider range of air-fuel ratios associated with Electronic Fuel Injection.

The use of Electronic Fuel Injection requires increased electrical flow, and the AC magneto now uses lightweight rare earth magnets that help raise output at 5,000rpm from 365W on the 2001 model to 448W on the new R1.

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