Difference between revisions of "Kawasaki KR250"
m (no summary specified)
|Line 34:||Line 34:|
Latest revision as of 00:21, 31 July 2019
The KR series were very successful Grand Prix motorcycles that dominated the 250 class, winning the World Championships five times from 1978 to 1983, when Kawasaki discontinued racing the 250/350cc machines to concentrate on the 500/750 classes. A 350cc version of this in-line twin also captured four World Championships. The inline or tandem engine design gives a narrow width that increases cornering clearance and reduces frontal area.
Development[edit | edit source]
Kawasaki designer Nagato Sato started work on the first KR twin during 1974 adopting an inline layout in order to minimise the width and thus the frontal area of the machine whilst still being able to utilise disc valves. The liquid cooled engine was housed in a conventional twin loop steel frame with twin rear shock absorbers. The machine first appeared in competition during 1975, often with Mick Grant in the saddle continuing into 1976. These years brought little in terms of success, but provided a wealth of information and the opportunity to develop the fledgling racer. 1977 marked a turning point for the twin and Kawasaki when Mick Grant secured the firms first Grand Prix win in the 250cc class at the Dutch TT at Assen and followed that success with a win at the Swedish Grand Prix later the same year.
The following season saw Kork Ballington, Greg Hansford and Anton Mang joining the team, with Hansford securing 2nd place in the 250cc Championship and Mang taking fifth, both securing Grand Prix wins in the process. Good as these results were they were overshadowed by Kork Ballington's performance, with victory in both the 250 and 350cc World Championships, a feat he repeated again in 1979. Mang took both the 250 and 350 crowns in 1980, Ballington second and Jean Francois Balde third (in both the 250 and 350 classes). Mang repeated his success in both classes for 1981 and narrowly missed a "hatrick" of doubles in 1982 securing second place in the 250cc championship and winning the third. For the 1981 season Kork Ballington concentrated on the 500 class with the Kawasaki KR500, leaving Jean Francois Balde to partner Anton Mang in the quarter litre and three fifty classes.
Kawasaki UK chose to celebrate the factory's fantastic racing achievement, not by importing the new KR250 but by releasing a limited-edition lime-green-and-white version of the dreary Kawasaki Z250 four-stroke twin (excuse me while I just go and be sick...). The KR was never officially imported by Kawasaki UK - however, in 1984 the enterprising manager of the franchised dealer Huddersfield Kawasaki decided there was a small market for this high-tech machine and brought in just 18 bikes himself and offered them for sale in his shop. This was possibly the first UK example of 'grey-importing' that was to become so popular later on. It was priced at £2799 which was exactly the same price as the officially imported GPZ600R alongside it in the showroom. Its rivals in the marketplace were the similarly-exotic V3 Honda MVX250 and the more conventional Suzuki RG250 Gamma. Yamaha's TZR250 was still some way off, their nearest comparable bike at that time being the first RD350LC YPVS.
The original 1984 model was designated 'A1'. In 1985 the 'A2' replaced it - the changes were limited to an upgrade of the primary gears. There are small differences to cater for the legal requirements of the importing countries so the Australian/New Zealand models have a longer rear-mudguard, fairing-mounted mirrors and separate indicators on stalks instead of the small square integrated indicators on the Japanese and South African models. The 'Huddersfield 18' came from South Africa I believe and others have since come in direct from Japan so all bikes in the UK seem to be the same. Standard colors are green/white, silver (with a red seat), white/red, black/red and red/grey. I don't think the KR has any kind of deliberate power or top-speed restriction - if you know different please let me know.
A year later, Kawasaki released the KR250S. It was the same as the 1985 'A2' model apart from the addition of 'KVSS', Kawasaki's version of the 'powervalve' system. The objective seems to have been increased bottom-end power as it appears to have no effect above 7000rpm. The 'S' also had fairing-mounted mirrors (instead of bar-mounted) and was available in black/red and blue/white.
Kawasaki KR250 Specification[edit | edit source]
- Engine 249cc (56.0 x 50.6mm) watercooled 180º tandem-twin two-stroke
- Rotary Reed Induction System with Mikuni 28mm flat-slide carbs
- 6-speed gearbox, vertically-split crankcases
- Chassis Aluminum square-section double-cradle frame
- UniTrak rear-suspension (adjustable damping and 5-way preload) with underslung (extending) shock and braced aluminum swingarm
- Air-assisted 35mm forks with 3-way adjustable AVDS anti-dive
- 100/90-16 front & 110/80-18 rear tires, cast alloy wheels
- twin front 260mm and single rear 240mm disc brakes, single-piston sliding calipers
- Dimensions 2.035m (l) x 0.685m (w) x 1.185m (h), 1.360m (w/b), 0.790m (s/h)
- 27º rake, 84mm trail
- Performance 45bhp @ 10,000rpm, 26.8ft/lb @ 8000rpm