Sunday, 17 November 2019
Kawasaki Z650
I'd probably done it again. Let my first impressions run away with me, been taken by motorcycle lust at first sight and handed over the dosh with hardly a second thought. To be fair to myself, the 1980 Kawasaki Z650 had been given a fresh coat of paint, had no signs of rust and its engine cases had been stripped of lacquer and buffed up to a near chrome finish. The consumables were in good shape but the bike was ten years and 83000 miles old. The vendor assured me it had been rebored and fitted with a new camchain and tensioner.
The doubts came fast on the ride home. What had been a splendidly silent motor developed all kind of noises once the throttle was used in anger. Rattles, knocks, you name it and the engine did it. Also there were huge flat spots in the power delivery, probably down to the nonstandard four into one exhaust, which was surprisingly quiet. The single disc appeared not to work half the time, other times making noises as horrible as the engine itself. Despondency had settled on me by the time I reached home, turning to a dark depression when I saw the oil dripping from the crankcases.
The next day I stripped off the tank and peered into the depths of the engine after taking the cam cover off. Bit of wear on the double overhead cams but nothing serious. All eight valves were within tolerance and the camchain looked in good shape. The compression tester revealed the bores and pistons at the lower end of thé acceptable range. The spark plugs were ancient and swapped for a new set. The air filter, what was left of it, had many layers of crud, lacerated by randomly placed holes that looked like the work of a particularly insane gorilla. I replaced that as well.
There were still lots of rattles and knocks but I put that to the back of my mind, figuring that any bike this old had a right to make a few noises in protest at being thrashed. The gearbox still worked OK with only the odd false neutral upsetting my day, usually between second and third. Performance, even with the new air filter, was a series of surges, dead spots, and more surges. I had tried to balance the carbs but found it impossible, they were so worn that adjusting one upset the others. I had given up after about two hours. Their worn state was confirmed after filling up the petrol tank for the first time - about 32mpg! Bloody hell!
I had also replaced the front brake pads with Dunlopads, the originals had plenty of meat left but were cracked and scored. The surface of the disc was rough, in places it looked worn wafer thin. Goodridge hose was already fitted, along with a newish looking caliper and master cylinder. The brake still refused to function in a predictable manner and I was often left with just engine braking and the rear drum to retard progress. The front forks were fine, perhaps either refurbished or fitted from a later bike (there was a bracket for a second caliper on the other side of the fork). Whatever, they offered a nice balance between absorption of bumps and tautness, having none of the harshness or sogginess that I had come to expect from old Japanese fours.
The rear Girling shocks didn’t offer such a sophisticated ride but were basically sound, although they allowed the back end to rattle around a bit they tended to keep it on line. With the frightening front brake I dared not do more than 80mph in the first week. This was obviously unacceptable, so a used disc was tracked down after phoning around about two dozen breakers. With that fitted most of the noise disappeared and braking became better, although by no means good. A four finger grip was needed for even mild stopping and after an emergency stop from speed there was so much fade that it took me back to my learner days on an old, decrepit CB125 single.
Top speed runs needed a long, smooth, straight road. The nearby motorway proved ideal, many an early morning (read 6am) was expended testing out the Kawasaki’s speeding potential. The most I got on the clock was 130mph. I was impressed as hell by this until I was stopped by the police who told me I was only doing 114mph! Talk about optimistic speedometers. I didn’t know if I should have been relieved or annoyed. The police gave me a stern lecture but were called away to a pile-up further down the motorway. Somebody up there must be looking after me.
For a heavy old four the Z650 held its top speed with remarkably good stability. I am used to old Japanese fours and was pleasantly surprised by the mildness of the Kawasaki's weaves. It was, admittedly, a bit of a brute to swing through bends but combined good ground clearance with a front end that refused to shake its head regardless of how rough the road became or how fast the going got. Most of the time I found the Kawasaki a reassuring bike to ride fast.
In six months I did about 9000 miles with few problems once I'd sorted out the initial faults. Even the flat spots appeared less annoying than they once had and my hand muscles adapted to the huge force needed to operate the brake. Then a series of minor faults reminded me how many miles the beast had done. The swinging arm bearings went, providing some insights into living dangerously before the cause of the handling degeneration became obvious. Those replaced, the back wheel, a spoked affair, started collapsing, another disconcerting experience I am in no hurry to repeat.
Bulbs started blowing as the insulation on the wiring started rotting away. Starting became difficult, consumption of spark plugs frightening. Oil started pouring out of the engine as fast as I could put it in as various gaskets blew. The petrol tank had rusted away from the inside, literally held together by the thin layer of paint in several places. The steering head bearings started cracking up. The speedo and tacho almost simultaneously stopped working, as if the bike was trying to warn me off.
I attended to the more important of these faults as best I could, raiding breakers or bodging where necessary. The speedo was persuaded to work again with a replacement cable, so I was able to watch my gradual progress to the magic 100000 miles. As well as dropping oil, the engine was also burning the stuff. More ominously, great puffs of blue smoke were coming out of the engine breather tube. Fuel consumption dropped to 25mpg as the mileometer groaned past the 96000 mark.
I was still thrashing the bike everywhere like it was a nearly new item, still able to put 110mph on the clock and cruise along at 85 to 90mph. The vibes had always been a bit unpleasant, now they gathered themselves into a frenzy come about 6500rpm (the tacho was still out but I knew that 75mph in top corresponded to this figure) and became merely worse as higher revs were employed.
As long as the bearings were OK, handling remained predictable - I had quite a few dices with modern 550s and 600s who singularly failed to show me a clean pair of exhausts down twisty A-roads. After ten months, with 97250 miles on the clock, it was decision time. Sell the brute while there was still enough left on the clock, refurbish or replace the engine or dump the heap on the nearest breaker?
The Z650 still shone up like a three or four year old bike, so I thought I'd try the back pages of MCN. I'd paid £450 for the bike so put her in for £350, admitting that some attention was needed to the engine. God, the telephone never stopped ringing for about a week. The first guy to turn up on the doorstep handed over the money without even bothering to go for a test ride. If I had been less scrupulous about its engine condition I could probably have got double the money, but I was happy enough, I had enjoyed nearly 15000 miles at the cost of a couple of hundred quid. I always came back with a large grin on my face after a ride, either just a saunter along local roads or a weekend's minor tour across the country.
I always managed to make it home, even when things failed. I would definitely buy one with a lower mileage (preferably the twin disc model). Z650s are lovely old brutes that should be snapped up whenever the mileage and price is right - they hold their value well and can take massive abuse.
A.G.L.