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I needed some fast wheels quickly, had three grand to play with and a liking for Kawasakis. Past experience with horrible strokers have put me off those things for life, however much fun 350LC owners might have. A 1988 Kawasaki GPX750 was on sale for £3650 at my local dealers. I had a test ride was impressed and offered the dealer the dosh in used fifties. For £3000 it was mine, but with no warranty at that price and I had to sort out the worn out Yokohamas myself.
The ride home was made more interesting by a massive downpour. The worn tyres gave the bike a very skittish feel, the gearbox kept missing changes and the front wheel slid away from under the bike a couple of times. Luckily, the latter occurred at low speeds and a quick flick of the GPX had it back on course.
The next day I rode down to my local tyre discount centre and had them fit a Metz ME33 front and ME99 rear. I was not too impressed by this combination, the 16 inch front wheel felt very twitchy indeed and on long, fast straights once more than 90mph was on the speedo the bike weaved quite nastily. It's possible to get that speedo up to 150mph, the weave doesn't become any worse.
The GPX looks quite weird and does not inspire much love with the great unwashed. Those looks hide scintillating performance that will see off the latest 600s and give some 1000cc wonder bikes pause for thought, especially when some curves are involved.
Despite the twitchiness, the bike is very flickable indeed. My mates on their ridiculously outdated twin shock fours didn't have a hope of keeping up with me. In the wet it's extremely easy to lose the back wheel when accelerating out of corners and it's even possible to waggle the back end on straights! Great Fun!
After 3000 miles both the Metz's were wasted and the handling had become very dodgy. Next, I tried a set of Michelins, an A49 front and M48 rear. Much to my relief, these made the steering more stable and got rid of the weave until 110mph was up, although it did get progressively more frightening if you went any faster. Apart from the weave, high speed cruising was limited only by ones own regard for licence endurance as any speed up to the maximum wallop could be considered a suitable cruising velocity. The skimpy full fairing gave a surprising amount of protection if you were willing to wrap yourself around the machine.
I used the machine to blitz Europe a couple of times without problems, although the seat does turn to a plank after the first 250 miles. Cruising at the legal 70mph is a breeze, the engine feels like it is just ticking over and the fuel improves to around 60mpg, instead of the more normal 45mpg. Once or twice I managed to get it down to 40mpg, but this was really pushing things and equated to rushing around in the lower gears with the rev counter in the red.
Power delivery is very useful. There's little indication of the arm wrenching available at higher revs if you keep it below 5000rpm. Under those conditions, the engine is smooth, will pull high gears after a fashion and dead safe to ride in the wet. It would take off in second of you had a mind to and would roll forward just by letting out the clutch slowly without touching the throttle in first. It was so easy to ride that my woman was able to master it very quickly (more normally mounted on a GS125) and I found it very interesting to ride pillion with her ass rubbing up against my crotch.
Once 5000 revs are up the thing begins to wail nicely and by the time seven grand has passed it's all but trying to pull your body apart with the G- forces. Fast forward progress is somewhat spoilt by the sloppy gearchange and if I had a tenner for every time I've missed third to fourth I'd be very rich indeed. Despite sending the revs soaring into the red every time a false neutral has been hit, the sixteen valves have shown no signs of hitting each other. Thank God.
The bike had 15000 miles on the clock when I bought it and I've at least doubled that. I say at least because the speedo cables keep breaking so it's anyone's guess how many miles have gone unaccounted for. Engine reliability has been excellent despite the fact I've never looked at the sixteen valves, never touched the four carbs and have restricted my maintenance to changing both the oil and filter every 1500 miles. The coolant level has never even flinched. The four cylinder engine had been modified to stop carb icing and there was no sign of this.
The rear Michelin lasted 4250 miles and the front was almost finished as well. I next tried a set of Avon radials. A bit more expensive but there you go. The first few miles were jolly disconcerting as the bike felt like it was running on a very thin strip of rubber but they soon settled down. High speed stability was yet better with the weave gently coming in at 125mph and not becoming frightening enough to make me back off from 150mph. Most of the twitchiness had gone as well, although the bike had started to pogo about a lot as suspension at both ends was becoming shot.
One thing with the Avons, though, if you take your hands off the bars at low speeds, the bars twitch from side to side quite alarmingly but settle down as soon as you touch the bars again. Felt just like there was a loose bearing or bolt somewhere but it was still there after I tightened up all the bolts a little more. I played around with tyre pressures to no avail.
At about 21000 miles, the rear caliper seized up so badly I had to buy a nearly new one from a breaker. The rear brake had never been very good, taking ages to work in the wet and then locking up the wheel; I had some wild slides until I stopped using it. The front twin discs were powerful and needed loads of muscle to work - I like that kind of set-up as it provides a margin of error if you grab too much brake in panic. A complete set of pads lasts 6000-8000 miles depending on riding style.
The bike also began to require lots of polishing to stop rust breaking out everywhere. Tedious and time consuming. It was also necessary to check over the bolts from time to time. The engine was generally smooth, but full bore work brought out some pretty fierce vibration. Among other things, I lost two handlebar mount bolts, one footrest and an indicator lens. Perhaps Kawasaki were trying to appeal to old Norton owners.
I fell off twice, both low speed shunts when cars did weird things I didn't expect. I cracked the bellypan in one accident and bent the right handlebar in the other. The bar snapped off when I tried to straighten it, so it was welded back on, which with a bit of silver paint makes it difficult to discern. The bike tends to slide along on the plastic and indicator stalks, so is quite resistant to serious accident damage.
The back wheel bearings went at 27500 miles, no grease could be found so it's not surprising. I had already whipped out and greased various spindles in the back end Unitrack, so had no problems in that area. A new set of springs and set of gaiters were added to the front forks, which tightened things up nicely there. It no longer bounced up and down vividly whenever I hauled on the brakes at low speeds.
The radials have done nearly 8000 miles and are due for replacement, a mileage that more than compensates for their extra cost, although my slightly more mature riding style has given them a easier time than earlier tyres. They have become a bit vicious in the wet, the rear losing grip momentarily on a few occasions but they are impressive tyres.
If you can take the looks, the GPX is a most impressive motorcycle to own, great fun to ride and even more reliable than most modern Japanese fours. I was tempted to trade in for a newer bike, but the local dealer made such an insulting trade in offer that I gave up that idea. It looks like I will be keeping the bike for a few more years.
F.J.P.
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I went through a phase when on every take off I just had to wheelie the bike for 50 yards or so. I found the way the machine reared its front end controllably and rapidly was most impressive. When you're 18 and out to impress the world this kind of delinquency quickly takes hold. I was weened off this when, after 1500 miles, both the chain and clutch were shagged out.
The 1988 GPX600 was two years and 50,500 miles old when it came into my possession, generally in good condition and with a service history of sorts - the carbs and valves had been done every 10,000 miles and the owner had earnestly assured me that he had changed the oil every 1000 miles. The engine was a bit rattly but then that's how most watercooled, across the frame DOHCs Kawasakis sound.
My first impression of the machine was the way it accelerated, then the ease with which it could be flicked through fast bends and almost my last impression occurred when I then decided to find out its top speed. With 140mph on the clock down an empty, straight country road, a tractor rolled out from behind a hedge. An adrenalin inspired grip on the front brake lever had the forks plunging despite the anti-dive, whilst the back wheel locked up and skipped all over the road. The farmer looked up from whatever it was he was contemplating, slammed on his brakes, leaving me a foot, or so, in which to slip through on the bouncing Kawasaki.
As this occurred on my very first ride I made a note to think about what I was doing a bit more, then promptly forgot that by experiencing a series of hairpins that the GPX went around as if on rails. The seat leaves you low in the machine with that big hump of a tank between your knees and the bars a reasonable stretch away, not so high as to be instantly uncomfortable in town. I felt immediately at home on the machine and after ten minutes it was like I had been riding the bike for years.
The first 6000 miles went by with hardly any problems. Only a rear Metz that seemed to wear out as soon as it was placed on the wheel spoiled my happiness. A wider tyre was fitted which improved mileage slightly, from 4000 to 5000 miles. The front was slightly better at 8000 miles. I like the Metz's, though, they had great grip even in the most dubious conditions and endowed the bike with first class stability. I did ride a friend's GPX fitted with Pirellis but it felt very twitchy, so I think I made the right, albeit expensive, choice.
When I bought the bike it was still on original suspension, all turned up to their highest settings. With about 58000 miles on the clock, the shock was shot, allowing the machine to pogo over bumps and wallow through the curves. As the rear tyre wore down to the carcass the weaves became more pronounced and accelerating out of corners resulted in much wobbling of the handlebars. Before I got around to replacing the shock and the tyre, the machine had become really dangerous above 70mph. The transformation when the replacements were made was almost miraculous, the Kawasaki felt like a brand new machine.
Not for long, both the front calipers and anti-dive unit conspired to seize simultaneously. With just under 60,000 miles up, they all needed replacement. Thank god for breakers, as new parts were very expensive, although some items common to the whole range such as indicators and levers were rather more reasonable. The pads lasted about 9000 miles which I though reasonable as I tended to ride on the front discs a lot - my right-hand muscles bulge magnificently from all the effort required.
With 64000 miles under its wheels, the handling started to degenerate again. There are a couple of grease nipples on the Uni-track which I had occasionally attacked with a grease gun, there was no discernible movement out back. The front forks were not pitted and there were no leaks from the seals, so that end seemed okay. The problem slowly emerged as the wobbles became really fierce. After one white knuckle ride my only surprise was that I was able to come to a stop without suffering a heart attack or being thrown clean off the machine. When I tried pulling on the forks there was a slight amount of movement - the steering head bearings were on the way out again. Perhaps because I didn't fit Kawasaki bearings, the replacement only lasted 5500 miles.
By 65000 miles the engine was running rough and spitting back through the exhaust. I feared the exhaust valves were burning away, not having checked the clearances since buying the bike, but one look at the underside of the original exhaust with several holes in the downpipes convinced me otherwise. A bit of welding got rid of the popping noises but the motor was still running rough. Taking off the GRP was a real pain in the arse, then stripping off all the muck to remove the cylinder head and then finding all the valve clearances were perfect didn't fill me with amusement. The local dealer did a carb balance, as I didn't have the equipment, and the motor was running perfectly again.
It didn't, however, have much of an effect on fuel consumption. I managed to get it down to 20mpg on some well crazy occasions, although 55mpg is possible if you're in a moderate mood. Cruising at, say 90mph, down motorways returns 40mpg, doing over the ton gets it down to 30mpg. My friend's machine is a lot lower in mileage and does about 10mpg better than mine at the same speeds.
The bike is good as a high speed tourer. The riding position is comfortable and the fairing begins to make some kind of sense above 90mph. Below that it just helps direct a deluge of water over hands and head. A German autobahn dash at 120mph didn't perturb the machine at all and I was still able to stand upright afterwards. Sustained high speed work does take its toll on the chain, which stretches so much its needs adjustment every 300 miles. Mileage has varied between 2000 and 7000 miles depending on the level of abuse and quality of the chain.
A newly acquired girlfriend was soon perched on the pillion. She was nearly as tall as myself and towered over me because of the radically stepped seat. Judging by the way imbeciles pointed at me and hooted out obscenities it might have looked faintly ridiculous. After a 200 mile run she got off the machine, swearing like a docker and telling me where to get off. She stormed off towards the railway station and hasn't spoken to me since. Thank you very much, Mr Kawasaki!
Perhaps I will have to find a Japanese girlfriend, as apart from a midget they're the only sort of girl likely to be happy on the crunched up and uncomfortable pillion perch. The bike now has 76000 miles on the mileometer. There is a slight oil leak at the cylinder head gasket, it needs a half litre of oil every 200 miles and doesn't pull beyond 125mph. The clutch has begun to drag in town and the gearbox has become very crunchy, slipping in and out of third, fourth and fifth. The neutral indicator has ceased to function and neutral has become difficult to find.
Only last week I pulled up at a crossing snicked the bike into what I thought was neutral and revved the cold engine a bit - the box jumped out of neutral and leapt forward a foot before the engine stalled. The old dear who we had inadvertently attacked, picked herself off the crossing with surprising rapidity and was joined by her fellow old crones, who surrounded me as I frantically tried to fire up the GPX. When the engine finally caught it saved me from a real battering from the ancients.
The machine still looks neat enough, so I took it down to the local dealer and asked him about a trade in against a ZZR600. He offered me a thousand notes off the list price. I told him where to stick his offer and went off on a round of the breakers to buy some much needed bits for the GPX. Looks like I will be sticking with it for a couple of more years.
Chris Leigh
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32,000 miles had done quite a lot of damage to the 1988 GPX600. The camchain rattle causing the most concern if the rotten condition of the chassis was ignored. It still ran well enough to reveal that the chassis wasn't bent and that the motor still had some life left. £975 seemed reasonable.
£120 for a new camchain to be fitted combined with £150 for a respray left only a new sprocket and chain set to put the GPX to rights. Would've been a week's work had not the mail order company mislaid my order for two weeks. It went through the MOT without any bickering from the tester.
The respray had left the bike ice-white and grey, which helped out the square cut lines of the GPX. It was always a bit odd looking even by the standards of the day but at least the large white frontal area had the cagers shaking in their seats as I roared up behind. It was quite nice being mistaken for a police bike, with cars veering viciously out of my path.
Initially, this was just as well. The front brakes had appeared rather powerful in low speed stops, but a couple of emergency braking sessions revealed them to be entirely inadequate. The calipers' pistons were sticking on and off, making the forks judder like their bushes were shot.
The rear disc was even more horrible, sticking on solid, turning the disc red hot. I hurriedly pulled it off, suffering third degree burns for my pains. A huge amount of sludge thrown off the rear wheel had found its way inside. On disassembly it was found to be beyond repair. I reassembled it without any innards....
The front calipers were cleaned up, given new seals and a set of pads. The heavily scored discs were left as they were with the result that the brake worked well enough but made the kind of screaming fit imitative of a dog being run over by a car. The forks were still in good shape with a lack of looseness that would've served a new bike well, so braking was thereafter very controllable even in the wet, with plenty of feedback from the front tyre.
The GPX had a pair of Avon tyres (AM22/23) on its sixteen inch wheels which gripped the road well enough but there was a feeling of twitchiness from the front end. It was more nervous than violent, but never seemed entirely planted on the road, especially at the high speeds that the GPX was still capable of.
The Avons were not so good on wear as I'd expected, about 7 to 8000 miles. A ME33 and ME99 combination provided even more grip, enough to ground the pegs on the faster bends, but they lasted for less than 5000 miles the pair. Another owner suggested Pirellis but a good deal on a set of Avons made me go back to them. 16 inch wheels do go through tyres faster than larger diameters.
The chassis seemed strong enough, at least until the original shock finally lost all its damping and the Unitrak bearings developed a bit of slop. This is a common problem if the spindles are not regularly greased. Removing the swinging arm was only achieved after expending enough brute force to get me locked away as a mass murderer. Shock, spindles and bushes all added up to over a £100. The set-up really needs a strip and grease every six months.
The motor runs more reliably than the chassis. It's a lovely unit with a distinct character split, that is maybe emphasized by the Motad 4-1. Below 7000rpm it's relaxed and affable, although not if less than 3000rpm is employed in any gear between fourth and sixth. Taller gears revealed a lot of transmission slop, which was not, fortunately, mirrored in the smooth gearchange (although high mileage engines can be deduced from a grabby, vague box).
Hitting 7000rpm had the GPX snarling, spurting up the road, needing a quick dab on the gear lever to keep up with the rate the tacho needle swung around the counter. The GPX could be dismissed as old tech, these days, but it still had 85 horses and not much more than 400lbs of mass. Top speed was 145mph, which meant it could easily cruise at up to 120mph, although the feel of looseness at the front and the air blast streaming off the top of low screen made it a less pleasant experience than on some grand tourer.
The bars, pegs and seat all worked well for me. The pilot's perch was nicely sculptured and held me firmly in place. The big chunk of petrol tank between my knees helped me feel part of the bike. Someone fatter or longer of leg might complain about being rather cramped but I was happy enough for 200 to 250 miles at a time. I was also more than happy with the fuel, at 55 to 65mpg!
I was less elated when the replacement camchain went after only 14000 miles. This time I put in a new tensioner as well. Somehow, during the reconstruction, some wiring had been trapped between the engine and frame. The result was the ignition module going up in flames, which scorched some of the plastic and blew every fuse in the Kawasaki.
This all occurred as I was lumbering along some dual carriageway at 80mph. By the time I'd crashed braked to the hard shoulder, I was gagging from the smoke coming up from the bike. Panicked, I ran away from the GPX, thinking the whole lot was going to go up in one big fireball. The fire died a death of its own accord, but not before three police cars descended upon the scene like starved vultures. They couldn't think of anything to charge me with.
Kawasaki ignition units are not the most reliable bits of electronic trickery in the world, nor are GPX's the most common bikes on the road. Breakers just laughed when I asked them about replacements; the only one who agreed to sell me one sent me a unit that was already dead and refused to refund the thirty quid. As it was 500 miles away I had to put him on my death list for future retribution. I ended up buying a new Kawasaki unit. Sob, sob!
Other signs of frailty were evident in heavy smoking of the exhaust on starting up, the occasional carb off-loading a bowl full of petrol and some rattles from a clutch that was becoming a bit jerky. Engine maintenance consisted of an oil change every 2000 miles with a new filter at 5000 miles as well as a carb balance and valve check.
I did, on holiday tours, stretch things a bit further than that with no apparent ill-effects. Pillions were not too amused at their tiny perch and pegs placed perfectly only for midgets. It was impossible to secure a tank-bag properly and my throw-over bags took large chunks out of the plastic sidepanels and always threatened to turn into a fireball on the side with the rakishly angled silencer.
Pillions cursed the secondary vibes that strafed their feet, although it would take over 300 miles before the buzz had any effect on my extremities. Even after 500 miles in a day the effect of the vibration was not too calamitous. As a solo tourer it was fine, two-up was pushing the limits of the experience.
By the time 60,000 miles were on the clock, the motor had started to run rather rougher than normal. I carried on riding for another 3500 miles until starting became a ten minute affair. Diagnosed as low compression on two cylinders. By then the camchain was rattling again as well. Pulling the motor apart I feared the worst, but two sets of rings and a new chain put it back into reasonable shape. The plastic needed another spray job to get the whole thing up to spec, this time in the stock red, white and grey.
The six year old bike was obviously nearing the end of its useful life by then. I knew a point would come when so many parts would need replacing that the total cost, even using secondhand parts, would not make a rebuild a viable option.
I kept riding for a while, putting nearly 70,000 miles on the clock before having to spend out any further money. I'd started to find that around 90mph it'd weave wildly and wobble savagely if I was silly enough to go any quicker. These symptoms were finally traced to the demise of the rear wheel bearings. A coupe of cheapo items were hammered in; they would last long enough to pass the MOT and let me sell the bike before anything else went wrong.
This was perhaps a little ungrateful, but I'd grown a bit bored with the GPX during the past couple of months; I'd either become used to its performance or it was losing its edge. I only got £850 for it, but all things considered I reckon I'd had the best years of its life.
Mitch
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Speed was the only thing on my mind when I went to look at the GPX750. As an eighteen year old graduate of the TZR125 school of learning (derestricted to about 30 horses, natch), what else was there? Luckily, one of our mad number had sussed out the insurance dilemma with enough artistry to survive a cursory examination by the cops. So that major limitation was overcome; a potential horror that had severely slashed the cost of most 750's on the used market.
1989, 22000 miles, shagged chain, good tyres, loud exhaust, cracked plastic, faded paint and one hell of a kick in the guts from the DOHC watercooled four cylinder mill. After I stopped gibbering away, the ton on the clock through the town centre even shocking me as I tried to stay on the pillion, I said I'd have it. Another half hour of madness on the pillion to get me home where the loot was stashed. The old man nearly bit through his pipe when he clocked the size and power of the monster but seemed happy enough to drive the owner home in his Corsa.
Fortunately, my mates were off annoying the Scots for a couple of weeks, giving me the chance to get to grips with the big Kawasaki before I had to prove how much better I was than them. Fully tanked up the GPX weighed in close to 500lbs, which made the TZR feel more like a moped than a motorcycle. All the wild techniques I'd employed to keep the tiny Yamaha in the frame were worse than useless on the GPX. Bloody dangerous, actually, as the tiny front wheel let loose for no apparent reason, the rest of the substantial mass trying to throw the bike off the road.
With the big Kawasaki I had to finish the braking before I threw the thing into corners. It was generally stable, at least in a straight line and through fast sweepers; ideal as a fast motorway missile. Up to 120mph, that is. After that stimulating velocity some strong secondary vibes came in that had the pegs and bars rattling away, not unlike the time the TZR's main bearings were on the way out. 140mph came up with a bit of a struggle, some weaves and a rather uncomfortable racing crouch (the screen being low enough to throw water into my chest under normal riding).
The life of my licence hanging in the balance soon caused me to back off (although fake ones are easy enough to buy). The 150mph ultimate kick had to wait for my favourite back road route. The motorway was as smooth as British roads get, the back road a fine example of council neglect, based on the presumption that anyone who didn't use the A road was, anyway, asking for it. The GPX, mass apart, had appeared pretty finely balanced to my juvenile mind. No-one would call it anything other than a bit of a pig in the serious twisties but lacking any of the danger found in old seventies' fours. I'd had a right laugh when some old codger on an original CB750 rode off the road when I'd cut inside him on the TZR.
Little did I realise that fate has a way of getting back at such recklessness. There I was, all gung-ho, absolutely revelling in the way the old Kawa rocketed through the gears, not seeming to slow in the least as the taller ratios were attained. 70, 80, 90mph all whizzed by...then the front end went a bit queasy as the ton was breeched. Next there was a total transformation of the handling, like the front end was falling apart. Lock to lock went the bars. Arms, already under pressure from the searing rate of acceleration, were close to breaking from the, er, macho handlebar wobbles.
At about this moment total panic set in. I'd experienced the odd wobble on the TZR - who hasn't - but nothing like the violence let loose by the bumpy road surface. Could this be what all the old hoodlums were muttering about H1's and Z1's? Panic resulted in me shutting the throttle and slamming on the brakes, the latter as effective as reverse thrust on a Jumbo without the trauma of the engine falling out. Old bikers will know that this natural reaction is the worst thing to do when a bike's in the middle of a speed wobble. The GPX reacted as if someone was shooting holes in the tyres, taking up the whole of the road in a feeding frenzy of wobbles.
We survived, but only at the cost of sprained wrists and running off the road on to grass verge. The GPX didn't like soft ground whilst trying to sort itself out but speed was down to about 30mph and my legs escaped being broken into pieces when I put both boots down to gain stability. Bloody hell, by the time we'd slithered to a halt, my whole body was shaking away like a druggie trying to go straight. I rode home as slowly as an OAP first time out on a moped. The solution to all the trauma was fifty notes on a steering damper. Apart from the time I blew a similar amount on a Negro hooker, the best value for money I've ever had. I don't know how the old owner survived without one.
This all sounds very nasty but it was the one really foul moment that I've had in two years and 27000 miles of hustle and bustle. We could throw in the rattling camchain at 43000 miles, as another, but there was plenty of warning and I didn't really begrudge the £120 it cost to fix.
Engine reliability was brilliant, despite being thrashed as if I was still on the TZR. Oil every 1000, carbs every 2500 and valves every 6000 miles, with the odd set of spark plugs to keep the starting up to scratch. It's not an ideal short hop commuter because the motor takes a good ten minutes to warm up; when cold there's quite a bit of stuttering and sulking. Maybe that's down to the open pipe but it runs really well once warmed up. A sure sign that it's running lean is the 50 to 55mpg - better than the TZR!
Some friends have complained about the gearbox being notchy and going off with a bang when first's engaged on a cold motor, but it's never really bother me. As long as the rear chain's in good shape. Old ones turn up a lot of noise and vibration in the transmission. I never managed more than 7000 miles out of a chain; worse still, the sprockets were also thrashed. I recently replaced the cush-drive which has made a major improvement in the transmission, maybe the chain will last longer this time around.
The secondary vibes did eventually turn the cracked fairing to dust, bits spraying off the machine one nice summer evening. The one bit of replica plastic I looked at seemed so wafer thin that I doubted it would last for a week! A similarly cracked top fairing was purchased from the local breaker for thirty quid and successfully patched up (i.e. it hasn't fallen off yet) and painted bright white (scares the shit out of cagers, can't wait to get a noddy light).
At about 50,000 miles the bike went malevolent in the wet, cutting out, surging in; wild slides and a short-cut to a sojourn in hell. Coils on the way out, used ones sufficed. Putting the leads on the wrong way around led to half a day of cursing until I finally realised what a stupid plonker I'd been. We all have these moments when the brain takes the day off.
Currently, the old gal looks a bit worn and beaten, rattles like a BSA Bantam, and won't do more than a 140mph. The taut suspension's still stock and the brakes haven't been touched except for pads (although they were uprated with Goodridge hose and had been rebuilt by the past owner). I don't do that much riding in winter. Rubber's a bit of a problem, what with sixteen inch wheels being old hat now and tyres being shredded in less than 5000 miles. I fit whatever's going cheap and can't say I've noticed much difference between makes - I do take the bike to its limits whenever I can.
Two years with the GPX has taught me to respect its power and mass. Also that experience and effort can get such an hefty hulk though the curves pretty damn rapidly - I've been known to wobble around the outside of devices like CBR and FZR 600's. And, I'm still here to boast about it, so there!
Seriously, though, The GPX is a bit of a hefty step up for a 125 graduate (especially one used to a mere 12hp), with a whole different level of power and handling to explore. The bike really needs revs to fly but runs cleanly if slowly below seven grand, so it's possible to take it gently for a couple of weeks. However, to the average teenage male, OD'ing on an excess of hormones, that's as likely as getting them to wear a condom the first time they take a virgin. You want to wave two fingers at society, kid, then the GPX's where it's at on a limited budget - mummy, I want a ZZR1100.
JD
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I'd just sold my BMW R60 for £1500 and was in no hurry to make any rush decisions in respect to a replacement steed. However, scanning the classifieds I noticed a red and white D reg Kawasaki GPX750R for £1900. I viewed the bike, test rode it and offered £1700 (already £200 over budget). The owner refused in no uncertain terms so I left forthwith but not before handing over my phone number, just in case. Sure enough, I had only returned half an hour when the phone rang and the erstwhile owner said it could go for £1750 but no less. A deal was struck!
The bike was in desperate need of a new set of consumables - chain, sprockets, tyres, rear wheel bearings, oil and filter change, fork oil seals. As I was already broke, replacement of the various worn out bits was carried out on a methodical and practical analysis basis - if it could last a bit longer it was left.
The first things to be replaced were two rear wheel bearings and both tyres. The bearings came free with the bike, the tyres I had to buy, gulp! I removed both wheels and took them to JC M/C Tyres in Derby - excellent place - and had Conti TKV's fitted at a total cost of around £100.
The existing tyres were Dunlop Sportmax radials. As this had been my first experience with sporty super grippy radials, I was most disappointed to find their grip and longevity was only as good as other well known cross-plies at two-thirds of the price. If you pay £100 rear and £80 front you at least expect them to grip. My previous experience with Dunlop Arrowmaxes on a CBX550 and a CB750KZ had also indicated that they were, er, crap. In the dry their grip was at best adequate, in the wet they were worse than a cheap and cheerful Chen Shin front tyre on my BMW. Back to the new tyres. The front was excellent for grip, the rear not quite up to putting down the power.
I checked the oil, finding it dirty. The previous owner had told me that the bike had been run on Putoline synthetic oil and changed every 2000 miles. Have you ever priced synthetic oil? I eventually paid £21 for four litres (yes, not even a gallon) for Motul synthetic. I then found that the very quiet Micron 4-1 exhaust had been designed by a college graduate and not a mechanic, the pipe ran directly underneath both the drain plug and oil filter cover.
To remove the exhaust you have to remove the fairing, radiator and possibly the oil cooler. I say possibly because I took the bike round to my parents and got my dad to flex the exhaust pipe down by an inch with his foot whilst I frantically removed the plug and filter housing.
With the oil replaced, new rear wheel bearings and new tyres, it was time to take it out for a proper test ride. The bike previously had a noticeable straight line weave at 90mph plus speeds and I'd assumed this was due to the rear wheel bearings being shot. The test ride revealed that the tyres needed scrubbing in as usual and the straight line stability was improved up until 115mph plus speeds. Cornering was predictable and fairly quick steering with the sixteen inch front wheel.
The bike could also be braked in mid-corner without running wide. Fast A-road riding showed up all the bike's bad points, on fast bends speed wobbles were always a problem when riding solo. On board, the feedback suggested that the swinging arm and frame were both flexing in simple harmonic motion against each other. Some journals advise fitting a steering damper but I didn't see the point (or have the money) when the steering didn't seem to be causing the problem.
With a pillion on board the bike's handling was almost transformed to an acceptable level. The rear shock has four hardness settings. I found to suit my size and build (6'2'' and 13 stone) that number one setting was most suitable and number three setting for pillion riding.
One particular ride I will never forget was a return journey from a relative in Leeds. I was following a rider with pillion on a C plate Yamaha FZ750 and could not keep up with him on the bends after 100mph (private motorway), not because the bike didn't have the necessary power but because the rider wasn't sufficiently trained in the art of bronco riding and was also struggling to prevent the bike from using other lanes of the motorway (well, that's what you pay your road tax for).
So, I settled for a steady 90 to 100mph cruising speed, being overtaken only by big Merc's, BMW's, reps in anything and, of course, plumbers in Astramax diesel vans trying to better the land speed record.
The actual engine's a gem producing 90 plus horsepower. The choke's typically Kawasaki, on or off, but it doesn't take too long to warm the engine up. There are two distinct powerbands, the first at 5000 revs and the second at 8000. The motor's very smooth and exceptionally quiet, to the best of my knowledge very reliable Carb balancing's needed every 5000 miles (£25). In my humble opinion, the engine is the best thing about the bike .
The quality of the frame and cycle part varies. The paint bubbles and drops off the wheels. Otherwise, paint finish's very good. The swinging arm has four grease nipples, a nice touch. The rear shock's harsh and gets worse with age. Expect a replacement to cost in the region of £200. The fairing's good quality but very expensive to replace - Kawasaki plastic screen £128! Pattern part £23. As the bike was only manufactured for three years don't expect too much help from breakers. I eventually got round to saving £80, bought sprockets and an O-ring chain, the type fitted with a split link as I didn't fancy stripping the swinging arm.
Some publications have said that the brakes aren't up to modern standards but I found them more than adequate. The front twin discs and single rear were progressive and still able to lock the wheels up if pushed - how powerful do you want the brakes to be?
I eventually sold it for the same amount I originally paid after 3000 miles when I experienced a very nasty speed wobble and also realising I would have to fork out for more new tyres, brake pads all round and an oil/filter change. I simply couldn't afford to run it and live with its poor handling. If a bike is capable of 150mph, it should be able to go around smooth corners above 80mph without wobbling.
Yes, the steering head bearings were new, lubricated and adjusted correctly; both fork legs had the correct grade and quantity of oil whilst the seals were oil tight; the wheel and swinging arm bearings were in good condition; tyre sizes and pressures were correct; the bike ran true when ridden hands off, and there was no previous crash damage or indications of a cracked, twisted, bent frame. The more people I spoke to the more I'd get the same response - they all do that.
To summarise: Rear tyre 3000 miles; front tyre 4000 miles; brake pads front 5000 miles (guess), rear 8000 (guess); O-ring chain expect 8000 miles plus if well lubricated; fork seals at least once a year; fuel 30 to 50mpg, average 40mpg; top speed around 150mph.
I hope I haven't painted to dull a picture of the Kawasaki. If I had been three or four stones heavier I don't believe the bike would have behaved so badly. Would I have another one? No! Would I have a GPX750 engined motorcycle if it handled well? Definitely if my bank balance could stand it.
For the record, the fastest speed I ever achieved was 135mph (another private road, officer) and the bike was still accelerating strongly. The problem with a fast bike is no matter how sensible you think you are, you will probably use the available power whenever you can on roads which are both unsuitable and have speed limits. I find on my present steed I can have more fun at safer speeds (and its a lot cheaper). Before the suspense overwhelms you, my present bike is an immaculate Yamaha 350LC Powervalve, an H reg with 6000 miles on the clock. This one goes round bends. But as they say, that's another story.
R.Roberts
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