Yamaha just moved the goalposts in the litre-class sports bike wars with a totally redesigned, third-generation YZF R1 for 2004. Right at the top I'll give you the two essential numbers:
134 kiloWatts
172 kilograms
"Wow!" is right.
The first figure comes from an even higher-revving 998cc, five-valve, transverse four with the previous motor's bore punched out to 77mm and its stroke shortened to 53.6mm – the result: maximum power at a stratospheric 12 500rpm.
The exhaust system is routed under the seat, a la Ducati, for maximum ground clearance
The compression ratio is up to 12.1:1 with bigger valves in the narrow-angle combustion chamber but a new closed-deck cylinder block reduces the cylinder pitch so that, although the bores are three millimetres wider, the width across the motor has increased by only 2.8mm instead of 12mm.
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The new fuel-injection system has motor-driven secondary throttle valves to reduce the slamming-door effect common to all spritzer-fed bikes with a 32-bit ECU for more responsive power delivery. It's also 27mm narrower than the previous set-up.
The clutch and six-speed gearbox remain vertically stacked behind the motor like all R-series Yamahas; not the best layout for a motorcycle transmission but it is definitely the most compact so lends itself to Yamaha's design philosophy of a long swing-arm inside a short wheelbase.
There's a high-efficiency curved radiator and a liquid-cooled aluminium oil cooler, direct-ignition "stick" coils integral with the plug caps and a high-output magneto for reliable ignition even when each plug is firing more than 100 times a second.
The motor is tilted forward so the main frame spars go over the motor instead of around it.
The exhaust system is routed under the seat, a la Ducati, for maximum ground clearance (Yamaha claims 56 degrees) and is all titanium, including the revamped EXUP valve, except for a stainless-steel mid-pipe containing the catalyser which runs too hot to be housed in any other metal.
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