It’s a family affair
The GPZ1000RX has an interesting place in the lineage of range-topping Kawasaki sportsters and sports-tourers.
It all started with the daddy, the GPz900R, known as the ‘Ninja’ in the USA.
This could arguably lay claim to being the birth of the modern Japanese sportsbike. Armed with a top speed of around 150mph, to get to that speed the GPz900R used a 115bhp, 908cc, liquid-cooled 16-valve inline four which set new standards in the class. Overall, the bike became the yardstick by which all other sports machines were measured as it handled, too. The chassis was a diamond steel spine, with conventional forks and Kawasaki’s Uni-trak rear suspension and 16in front and 130 rear-section 18in rear wheels. This would change to 17in front and 150 rear-section 18in rear for the A7/8 versions from 1990-onwards. These versions (effectively using the later GPZ1000RX’s front-end) also moved from the small z to a cap Z to differentiate the liquid-cooled 900R from earlier air-cooled Kawasakis.
From launch the 900R had kudos in spades, thanks to Isle of Man TT wins and the fact that in 1986 it appeared in the movie Top Gun. Of course, it was overhauled in many areas by the Suzuki GSX-R750F of 1985, but Kawasaki changed tack with the 900R’s replacement – or rather it’s stablemate, the GPZ1000RX.
The GPZ1000RX would see changes to the basic 900R’s motor to increase capacity to 997cc, giving a useful 10bhp increase over the earlier bike at 9500rpm. Chassis-wise, in came a perimeter (not spine) frame with more modern suspension and wider rubber at the rear (now a 150 rear section).
Back in early 1986 the 900R cost £3549 compared to the 1000RX costing £4099 and, to a degree, they were doing different jobs. The 900R was 10 kilos lighter and had the shorter wheelbase; the 1000RX was definitely more of a high-speed sports-tourer. In tests from the time many journalists continued to prefer the more nimble 900R.
Still, the RX blazed a trail as the fastest production bike then built between 1986 and 1988, when it was replaced by the ZX10 ‘Tomcat’. The ZX10 was a logical progression of the RX, and itself lasted only between 1988-1990. For this model in came a first for Kawasaki: an aluminium beam frame and other improvements on the 1000RX. Once more the 10’s motor could show direct lineage from the GPz900R, but with improvements around 135 ‘claimed’ bhp was available at the crank.
The ZX10 was ultimately laying the foundations for the longer-lived ZZ-R1100 and later ZZ-R1200 so for that we should be thankful – even to the RX itself. Interestingly the father of the 1000RX, the GPz900R, outlived both the RX and Tomcat by some years. In the UK you could still pick up a GPZ900 into 1993/4 while it carried on in the Japanese home market until 2003!
Price-wise today, all these old 16-valve Kawasaki beasts are still on the lower side of the price spectrum, but – as seen by this RX – like other bikes, prices are heading north. Bizarrely, the 900R still isn’t holding mega-strong money, but projects are found for a grand with decent bikes approaching £3k. Doug bought his RX for £1800 and reckons it’s worth around double that now – we’d agree. If you like the later bikes, a Tomcat can be yours for as little as a grand, rising for a cleaner example, while the ZZ-R1100 D (first model with single ram-air snout) comes in at around the same sort of price. Prancing ponies have never come so cheap!