2004 ZX-6RR gets major updates

Published: 02 September 2003

KAWASAKI has answered the prayers of racers around the world by updating the engine, fuel injection and chassis of its track-biased ZX-6RR.

The RR was launched into the ultra-competitive supersport class with an array of technical firsts – radially-mounted front brakes, a slipper clutch and an adjustable swingarm pivot mount – but it has only managed to win one World Supersport race all year.

The main problem has been extracting reliable horsepower from the 599cc motor which started the season very underpowered compared to the Honda CBR600RR and the Yamaha R6.

Blow-ups were common in the early stages of the season and it took until the Misano round of the world series in June to win a race.

Both factory riders – reigning world champion Fabien Foret and Spaniard Pere Riba have spent the entire season complaining about a lack of power against rivals from Honda, Suzuki and Yamaha.

The changes to the 2004 engine are aimed at bringing the bike back to the front of the field and include: A new cylinder head with bigger valves and revised cams, A new twin-injector fuel injection system, A revised close-ratio gearbox, A matt-black painted frame and swingarm, Revised front suspension with a new anti-friction coating on the forks, And an ‘all-important’ lime-green painted chain

All of the engine changes have been aimed at getting more power from the motor at the very top end of the rev range.

Kawasaki has also lifted technology first seen on the Suzuki GSX-R1000 with breathing pathways cut into the cylinders to reduce " pumping losses " and improve crankcase breathing at high rpm.

Both camshafts have even higher lift at the top of the rev band. World Supersport tuning regulations only allow for cam duration to be changed – the cam lift must remain identical to that of the homologated road bike.

No price has yet been released and MCN expects the new ZX-6RR to make its public debut at the Milan Show next month.