Friday, 28 December 2018

Kawasaki GPX250


What happens when the bike you've just handed over £1500 for splutters to a halt half a mile from the place where you purchased it? After wheeling back the disgraced GPX250 to the opulent detached residence I was met at the gate by the vendor accompanied by a pack of howling wolf-like creatures. In the darkened street, neon glow of Manchester he looked like nothing so much as a third rate Dracula. I expected fangs to sprout at any moment. ”Sorry mate, sold as seen,” were his last words as he rushed back to his coffin.

Come to think of it, the GPX has a certain vampire style with its black finish and complex array of angular lines. And it had spluttered to a halt just as we crossed a river! Nothing for it but to phone pater and arrange a lift in the back of his Transit. Back at our far from opulent two up, two down, the lower half of which was used illegally for the various minor businesses we were involved in, as well as a workshop, a lack of compression in the left-hand cylinder was soon diagnosed.

The pistons rings were broken but luckily the bore was not scored. Having to buy a complete new gasket set just for the top end bits did not amuse me. The bike went back together OK, it was just a matter of sorting out the mass of parts surrounding the engine, making it a tedious business to pull apart and put back together. She roared into life third press of the starter and soon settled down to a neat, off-beat tickover.

Now the riding proper could begin. It was a 1988 machine with 13400 miles done already, in good cosmetic shape, although obviously the engine left something to be desired initially. Immediately, the machine was thrown in at the deep end with a mad dash down to London, motorway all the way there and back.

40hp from a 250 twin was impressive, even a watercooled, DOHC, eight valve one. This translated into the ability to cruise in the 80-90mph range, which just about stopped me being run down by the cagers. Top speed was an indicated 105mph, but to get that you had to bounce the valves through all the gears, the GPX showing a strong reluctance to go over 95mph in sixth, a speed it could equal in fifth.

Power delivery was entirely dependent on revs. The machine would run along at lower revs but opening the throttle, even in the lower gears, produced just an increase in intake roar and precious little acceleration. Only when seven, more often eight, grand was on the tacho did the machine come alive, the engine note becoming harsher and the motor smoothing out as the power came in with a surprising punch for a 250. I only weigh nine stone and the Kawasaki 350lbs, so the low all up mass obviously allowed us to make the maximum use of the available power.

At 90mph vibes were almost non-existent, thanks to the gear driven counter-balancer and the pistons leaping up and down out of phase with each other. At lower revs there was a bit of rumbling and drive line lash would intrude if you tried for less than 2000rpm in the taller gears. However, by the time I'd arrived in the Great City, one of the pillion pegs was hanging off, so Kawasaki obviously know how to isolate the rider from the vibes very effectively, but forgot to specify some lock washers for essential components.

Handling had been fine. Weaves were conspicuous by their absence and the rear Uni-track was able to cope with the most demented of road surfaces. With small wheels and light weight, flicking through curves was so easy that at first I tended to put in too much input, messing up the lines as I quickly corrected myself. The resulting series of lurches upset myself more than the chassis. I soon learnt to think the machine through corners, it required so little effort that I often thought the Kawasaki was taking on a metaphysical aspect!

In London traffic the little Kawasaki was ace, just so long as you were willing to play with the gearbox and throttle... after the ride down from Manchester I would have preferred something that could have been stuck in one gear and didn't need constant input, but in that kind of traffic it's either do or die... so, I did.

The ride back up, on the same day, was mostly in the dark. The GPX’s headlamp was adequate for 70mph cruising but I needed to do more than that. I ended up on the edge of the seat, able to track the general road path but not sure what the road surface was like. The first I'd know about some dead sheep in the way would be when I ran over them. I ended up leaving the bike in fifth and belting along at maximum revs, the traffic thinning as I left the south and the time went by. Back home, my backside ached, my vision was blurred and my wrists flopped around uselessly.

Still, I felt quite pleased with the reliability and speed the GPX250 had shown. A good night’s sleep sorted most of my problems. The next morning there was a pile of oil under the motor and the oil level had disappeared way below the minimum mark... the oil filter had been slowing coming undone and was on its last thread by the time we arrived home.

I bunged some oil in and pressed the starter. She came to life first go and sounded OK. That was a relief. The bike was thrown into a daily commute and some high speed weekend riding in the company of mates on much larger machines. I had to work the gearbox like my life depended on it just to keep them in sight, but the bike did seven months and nearly 10000 miles with just regular oil changes. Then problems started emerging again.

In fact, it was the original problem all over again. The left hand piston rings had disintegrated, this time sending bits of steel all through the engine. One valve was bent, the bore was deeply scored, the piston cracked, the crankshaft mangled, gears missing off the primary drive... the whole engine was a write off. I cursed myself for not running the engine in when I had the chance. It's always the same with Japanese engines, they give fantastic reliability until one little thing goes wrong, then that seems to upset the whole engine even when you go to the trouble and expense of repairing it.

There was no way I was even going to think about fixing the knackered engine, so bought a used one out of the breakers for 600 notes. I was assured that it had only done 7000 miles and came out of a 1990 bike. For once they were telling the truth, the new motor was both smoother and faster than the old one. The bike has now done another 11000 miles with no engine problems.

The same could not be said of the chassis. For such a light machine its consumption of tyres is astonishing... I don’t do wheelie or tyre shredding starts, so I can’t explain why it only gives 4000 and 5500 miles from rear and front Metz's. The chain’s slightly better at 7000 miles. It’s the discs that really got to me - pads in 5000 miles but calipers that seize up as soon as a drop of rain hits them.

And the Uni-track linkages had enough play at 19000 miles to cause the handling to all but throw me off every time I banked over more than a few degrees, as well as promoting vicious weaves at speed in a straight line. The shafts were heavily scored and there wasn't a smidgen of grease in sight in the whole of the back end suspension assembly. New bits were extortionate, so father was persuaded to make up some shafts and bushes for me. I contributed the tin of grease that disappeared in the reassembly process. On the good side, the original exhaust has shown no signs of disintegrating and paint finish was still excellent.

Fuel economy was reasonable, 50-60mpg, given the way the machine was mercilessly thrashed everywhere. It was always heavy on oil, a litre every 400 miles - a long hard thrash meant an eye had to be kept on the oil level. As a 250, it was cheap to insure and tax. It never seemed to need any maintenance, valves and carbs not needing any adjustment!

Overall, I like the GPX but could have done without the engine problems, doubtless a result of the way it had been thrashed before I bought the machine. I don‘t like strokers, can’t afford the insurance on anything bigger than a 250, so it looks like we are stuck together for the foreseeable future. There are better bikes but there are also a hell of a lot worse.

Eric McClane