Sunday, 19 December 2010

Kawasaki GPZ900


The first Kawasaki GPZ900 was a despatch hack with an incredible six figure mileage and an owner so ugly I couldn't deal with him. His horror at his own appearance had played out on the big Kawa, reducing it to rolling wreck status. I thrust five fifties into his hand and rode off into the night.

The next morning I couldn't quite believe that I'd bought such a wreck - in the bright light of the day it looked even more horrible than I recalled. Worse yet, the erstwhile owner phoned me up to see how I was getting on, suggested we meet for a drink. He kept phoning up for several weeks until he finally got the message. The mind boggles.

The forks sagged and the shock bottomed out, the Uni-track linkages were loose and the steering head bearings were way past their sell-by date. The motor still produced a strong dollop of power and torque, albeit with a huge excess of vibration and lots of mechanical clatter. Oh, the front discs were the only item on the bike to have been recently renovated!

The dangerous combination of power and chassis slack wasn't really mollified by the ability to stop on a dime. Every time I used the brakes hard, the whole front end shook, strange tremors running through the chassis. Returning from the highly illegal test blast I wasn't that surprised to find that various rotted chassis bits had done the decent thing - fallen off. Including the whole rear light/numberplate assembly!

I decided to give the chassis a going over then see how long the motor lasted. A couple of breakers provided most of the bits - there are still plenty of dead GPZ900's around. There isn't much to the spine frame and all I did there was rub down the rust and touch up with some Smoothrite. The overall effect of all this effort was to turn a rat into a well worn hack. Sporting used components from different colour GPZ's the bike was in desperate need of a coherent paint job but was never to get one.

An MOT, tax disc and insurance got me road legal. The engine couldn't be used above eight grand - too much vibration! The petrol tank felt like it was going to split in half and the single remaining mirror threatened to twirl off. That was still fast enough for licence confiscation and keeping ahead of the pack on the motorway.

The best that could be said for the handling was that it was neutral. Slow turning but basically stable. The riding position was quit comfortable, either in town or when going for it. The front brake was very vicious, had to be treated with great care in the wet.

I rode the bike with a death-wish and it didn't spit me off! The engine did fail, but not before I got 16000 miles out of it in total neglect mode, as per all good UMG addicts. A couple of valves broke up, fought with the pistons and spread the debris liberally right through the motor. Total mileage is unknown but I suspect it wasn't far off 200,000 miles.

By then the chassis had evolved into a reasonable semblance of usefulness but finding a replacement motor proved impossible. It was hard going to find any alternative engine that would fit into the chassis and I gave up eventually, pushing the thing to the back of my garage.

A few bikes passed through my hands until I spied an advert for a 39000 mile GPZ900. Three owners, the last having kept the bike for five years and selling to buy a TL1000 Suzuki vee. Sounded promising. The guy rode over to see me, took me for a blast and reluctantly let me have a go at the controls. The comparative smoothness of the bike sold me on it but didn't stop me getting a couple of hundred quid off the price for replacement of consumables and a marginally leaking petrol tank - cost 750 notes.

I was totally pissed off when a few weeks later the camchain started to rattle. I'd done a bit of speed testing, was really thrilled to put 150mph on the clock and thought I'd found a great buy. The rattling camchain didn't affect performance but wasn't helped by my tweaking the tensioner! A few weeks later, the local mechanic threaded a new one on to the old and pulled it through the engine.

Luckily, I treated the bike to an oil change the next day. Lucky because a bit of old camchain came out with the oil. I went back to see the mechanic, gave him an ear-bashing and got twenty-five quid back! I was somewhat tentative about giving the motor welly but after a few days I was back to maximum throttle.

The power would quite happily shred the back tyre if I pissed about with donuts and burn-outs. The chassis, which uses the engine as a stressed member, didn't seem to mind but needed a bit of muscle to really throw through the curves. I was already used to the needs of such 500lb mammoths and could scare the stuffing out of 600 replica riders, not to mention myself.

The front discs on this example weren't up to snuff, so I swapped over the calipers and master cylinder (which looked totally different) but it still wasn't as ferocious as I wanted. The front wheels and discs were swapped and I was in business. The discs on the newer bike were about a millimetre thinner than on the old one, were maybe distorting under heavier braking.

The next 12,5000 miles went by in a blitz of speed and madness. Then the Uni-track linkages went. This time the whole lot was seized up solidly and I basically destroyed the back end in removing it. No great hassle, my old stuff would fit - it's vital to grease everything up, that way wear is absolutely minimal! If riding through the winter it's a good idea to grease them up before and after the dark season.

A few thousand miles later performance went off and the exhaust began to smoke. I expected valve trouble but the cylinder head looked okay. Nope, it was a couple of the oil rings wearing out which was a major hassle to sort out. I knew far more than I really wanted to about GPZ900 engine internals!

Not being totally thick, I figured the engine was going to turn very expensive a few thousand miles down the line - it wouldn't pull more than 140mph and there was quite a frenzy of vibration between 7000 and 8000 revs. Sold the bike for 900 notes and bought another one, two days later, for 500 quid.

This one had a rattly motor and rotting chassis but somehow came with a new MOT and actually handled rather well. Turned out to have a very expensive White Power shock and some decent taper bearings in the steering head. The engine needed a new camchain and a valve regrind but the bores and pistons looked perfect!

The chassis was mostly upgraded from my fast depleting stock and given a bright yellow paint job. My mates soon accused me of doing strange things with bananas! I added some expensive, sticky, Metz tyres and got away with absolute murder. My mate on a 916 Duke was left open-mouthed when I out rode him through the bends - mind, my heart was fit to explode and I nearly fell off three times!

The various GPZ's that had passed through my hands all came with nasty looking and wild sounding 4-1's but I managed to pick up a standard exhaust system for seventy-five quid - new but a dealer clearing out old stock. This made the motor run harder and smoother, especially after I fitted a new air-filter.

After six months the bike was running better than ever! Tired of the banana jokes, I resprayed the GPZ in stock red and dark grey. Looked like it had just come off the assembly line - from a reasonable distance! This new found respectability hid some more engine troubles, performance was dying again and starting coming close to draining the battery.

The camshaft lobes were rather oddly shaped, missing some essential metal. Old model GPz's used to do this as a matter of course come 35-40,000 miles but later ones were supposedly sorted. Turned out some of the oil runs were full of accumulated crud! A pair of secondhand cams and some serious effort made the engine run better than ever.

I was soon back into the swing of things, riding the bike really hard to keep up with the ever faster 600 replicas. Despite the extra mass and old tech chassis I usually won out. My friends reckoned I was an accident looking for somewhere to happen and took bets on how long it would take to destroy either the Kawasaki or myself.

Time wasn't on my side and the winter weather eventually had me off. What appeared to be a nice dry winter's morning with a bit of sun in the sky actually hid the reality of some black ice. I'd mucked around with the fairing to vent hot air on to my kneecaps, giving the illusion of temperatures somewhat above zero. Talk about living in a dream world! The GPZ lost its front wheel when I was banked over and that was that; no way back!

The Kawasaki slid, flipped and then slid again into a brick wall - according to the old codger who picked me up out of the gutter. I had bloodied knees and elbows plus some deep bruises! The old guy was all bright-eyed and bushy tailed, his days so boring that anything close to carnage had him flooded with adrenaline. He regaled me with tales of a youth misspent on a Triumph Thunderbird. Then, with all the alacrity of the senile, he switched into a diatribe against the Japanese, reckoned that the Kawasaki's destructive dance was just desserts. He was lucky I didn't thump him!

The usual hassle with the men in uniform and getting someone to haul the bike back home. The plod spent hours measuring the gouged tarmac, not believing the black ice story (it had melted by the time they turned up) and hoping they could do me for dangerous driving! The old coger's idea of speed had them thinking I'd been doing the ton-plus. What a waste of tax payers' money!

As it happened, the GPZ's motor hadn't been ruined in the accident, but just about everything else had. I still had the spare frame and a few bits and bobs. This didn't add up to a complete motorcycle but with a bit of scrounging of mates' garages and the odd trip to the breakers I ended up with a minimal, street-fighter style, GPZ900.

Must've lost at least fifty pounds off the chassis. As I still had insurance, tax and MOT for the crashed bike I bunged its numberplate on to the resurrected machine and did a few test rides. It wasn't up to much; handled like a camel (a straightened GPZ600 front end obviously doesn't work well) and tried to bounce off the road above the ton.

Had plenty of odd looks and suffered loads of jokes about the machine's appearance. Sad, some people. Ran it for about five weeks until some lunatic offered me 500 notes and it was gone, along with the garage full of debris from past misadventures.

Its replacement was a GPZ750, the rare and unpopular brother of the 900. This was the proverbial one owner but had 68000 miles on the clock. Weighed almost the same as the 900 but was down on power. needed a few more revs but I couldn't feel much difference in the on the road speeds, the old 900 had become so tired that it had lost its edge.

I did about 4000 miles on the 750 with no real hassles then sold it to buy a ZXR11 - mind blowing! I kept giving it too much stick coming out of corners, ended up going sideways. Several accidents later and a large pile of commendations from the plod, I decided I'd better get rid of it before I killed myself. A sane and sensible Honda CBR600 followed, but I haven't found real happiness with it.

As to the GPZ900, I'd really love to get my hands on a genuine low miler. The GPZ marked the rise of high tech motorcycles and was the bridge between the old style aircooled bruisers and the current highly competent replicas. That makes it an interesting piece of motorcycling history but they are also a joy to play with even in these days of hyperbikes.

Mark Dunn