At 58 I am what is perhaps known as a mature rider. My '78 Kawasaki Z1000 is certainly now a mature motorcycle. I bought the bike as a nearly new bargain, the owner deciding he couldn’t cope with the power. This was 14 years ago, when I still considered myself in my prime. I scoffed at his fear, but 80 horses and 550lbs of mass were a dangerous combination back then. I have averaged about 18000 miles a year, so total mileage has added up to just over a quarter of a million! Somewhere along the line I got to grips with the beast.
Back in 1978 the Japanese had mastered the science of making reliable four cylinder engines, but not the art of making a decent chassis. Kawasaki learnt their techniques on such unlikely animals as the H1 triple, taking a while to get to grips with such complex subjects as high speed stability. The Z1000 came to me in completely stock set-up, including lethal Japanese tyres and high, wide handlebars.
The first day was enough to convince me that a radical shake up was required. A set of Avons, some flat bars and rear-sets soon transformed the feel of the machine. By today’s standards the riding position is almost laid back, but for the day it would have been considered very sporty. With more weight over the front wheel from this riding position, and the rider crouched lower, stability improved dramatically. The tyres actually managed to grip the road when the machine was leaned over.
The bike was fine up to about 80mph. After that lots of weaves and wobbles appeared. They became worse the more the throttle was abused. Also, the re-positioned footrests meant that the first thing to touch down was the centre stand prong, which tried to lever the machine off the road. Incredibly frightening! The centre stand was all but useless as I found it impossible to lever the machine on to it without wrecking my back. It was junked quite quickly. I had an hydraulic jack ready for tyre changes and chain adjustment.
The one time I had a puncture in the back wheel, the AA man was not too amused at the antics involved in removing the wheel. I had a spare inner-tube but no way I could fit it on my own. We ended up with the bike perched precariously on its side after removing the back wheel spindle. It really was a heavy beast to lever back upright. The AA man reckoned the next time he came across a similar case he would call for the recovery vehicle to take the machine home.
The bike was incredibly heavy to ram through the corners and also liked to be set up way in advance... touching the front brake when banked over was likely to throw you off and the back end twisted when the throttle was backed off. The narrow bars I'd fitted made it a heavy beast in traffic, I often ended up sitting in traffic jams rather than hustling through narrow gaps. As top speed was only 130mph and far too unsafe to maintain for more than a few moments, I initially thought I‘d ended up with the worst of all worlds.
The engine impressed with bags of torque, lack of oil leaks and a feeling of being bulletproof. The DOHC unit was derived from the earlier 900 Z1, which had soon made a reputation for itself as being extremely tough. 80 horses is chicken feed, these days, but there is a lot to be said for the pleasant way the Z puts down its power. When I'd sorted the handling I felt quite safe riding hard in the wet, which is more than can be said for some of the high powered, lightweight machines of today.
Not wanting to lose face by trading down, I persisted with the beast for the next two years in its stock state. Sudden poverty meant I could not improve its suspension, which to be fair never became any worse over those years - it was too naff to begin with. I could get as much as 55mpg if I rode the colossus gently but throttle craziness soon reduced that to a mere 35mpg. The average has worked out somewhere in the 40 to 50mpg range, although I did once manage 31mpg. That was a really fast, flat out motorway bash with the Z1000 leaping about all over the place. My arm muscles were wrecked after a couple of hours of that kind of insanity.
Vibration has always been apparent as there are no balance shafts in the engine and little by way of rubber insulation in the chassis. It doesn’t cause any damage to the bike, but can reduce feeling in hands and feet after a couple of hours at high speed. 70 to 90mph cruising is okay for as long as the fuel holds out, although 60mph in fifth can be almost as rough as a 100mph. I can’t say it has got any worse over the years, but that’s probably me just getting used to the Kawasaki.
The engine whirred away reliably for nearly 40000 miles during the first couple of years. It needed the odd shim job on the valves, a couple of carb balances, a few adjustments to the twin contact breakers and the usual regular oil changes. Unlike its smaller brothers, the Z1000 has a hefty roller bearing crankshaft and gear primary drive, neither of which were to give any trouble over the whole period of ownership.
By the third year my finances had improved, so I set about upgrading the suspension. First priority was a set of taper roller bearings in the steering head. The old bearings were pitted and difficult to set up so there was no slop. These new bearings had a remarkable effect on the stability, pushing the weaves and wobbles up to about 95mph. As far as value for money went, they were by far the most effective improvement I made to the machine. These bearings have a life of about 35000 miles.
Encouraged, I put a set of needle rollers into the swinging arm, the rotten old ones having developed a dangerous amount of slop. It helped tighten the back end up, lessening the amount of twittering when rolling off the throttle. Life of these bearings was never more than 25000 miles, more usually around 20000 miles. With just these two changes I found it possible to cruise along the motorway all day long at 90mph, with brief bursts up to 120mph. The Z1000 was still potentially dangerous, though, certain combinations of speed and bumps causing it to twitch.
In this form I did a couple of long tours on the bike. As I had fixed the riding position to suit me to perfection, I was quite happy doing 400 to 500 miles in a day. Even if the seat was far from perfect, the clutch would start to drag badly and the vibes sent my feet dead. Without a fairing, wind blast above 90mph was rather tiring but when I was on an empty motorway I could not resist opening up the throttle.
On a very long road it was possible to put 135-140mph on the speedo. The aforementioned handling deficiencies and huge pain in my neck muscles meant I could only hold on to such speed for a few minutes. Still, it was a pretty exhilarating experience and gave fresh energy to see me through the rest of the day.
The front suspension was next on the list. Stiffer springs and thicker oil didn’t make that much difference to high speed stability but gave the machine a much more taut feel. A set of Koni shocks had more effect, allowing the machine to hit the ton without so much as a mild weave. The bike was still heavy and ponderous, becoming brutally twisted up at really high speeds. The forks are still there, gaiters have ensured that the chrome has not pitted. The shocks last about 30000 miles before they go off tune.
By about 50000 miles some major expense was involved. The back wheel had started breaking up, so | had that and the front wheel refurbished with HD spokes and alloy rims. The wheel bearings were showing signs of wear, so a new set was bunged in - life of the wheel bearings has varied between 50000 and 72000 miles. Also, the four into two exhaust had become rather loud, with cracks appearing in the silencers. I had a mate with a tube bender, so we made up some 4 into 1 downpipes out of stainless steel and put a universal mega on the end of it.
We found it impossible to set up the carbs to suit this device, so handed the machine into a dealer for jetting alterations. The result was that the Z needed ten minutes to warm up but made more power right through the rev range. It was also a lot noisier and makes a lovely bellow with 140mph on the clock. The lighter wheels and exhaust saved 35 to 40lb. I started looking for other ways to save mass, getting so into it that I started drilling holes through bolts and screws to lighten them.
As the seat was seeping up water I took that as a sign to make a new one with a GRP base and some heavier foam that would not flatten after a mere 80 miles of riding. Plastic guards, cleaning up the back end, dumping the indicators and throwing away the grabrail were other minor ways of removing some mass. When I took the machine to the local weighbridge I was surprised to find that all my efforts had reduced the mass to 480lbs (with about two gallons of fuel on board).
The Z has a massive frame that doesn’t bend in minor collisions, so even more could be saved if this was replaced with a more modern lightweight structure, although I rather like the reassurance of having a bike that can take the odd meeting with the tarmac. All my crashes have been at low speed when the mass has got the better of me or when | couldn‘t get out of the way of some clown in a car fast enough. Nothing more than a few bent ancillaries were the result plus a few bruised bones. Not bad going for the kind of mileage I’ve done.
I'm still not sure about the brakes. When I first had the machine these triple discs were exemplary in the dry and just about passable in the wet. Pads lasted a reasonable 12000 to 16000 miles and the calipers didn’t give any trouble for the first 35000 miles. Then they started seizing up something chronic, needing attention every 5000 miles. After 55000 miles they were replaced with a new set, which lasted 60000 miles. I’m on my fifth set now! The discs are still usable. Modern pad compounds improve wet weather feel at the expense of reduced life (8000 to 11000 miles) and some almost unbearable screeching noises.
One thing I hate about discs is the way the pads drag on at low speeds. Pushing the Z_backwards is a real trial of mind over matter. I once had to push the beast two miles when I ran out of petrol, having left the petrol tap in the reserve position. I almost collapsed from the pain of it when the petrol station finally came into sight. I had to sit by the roadside for half an hour just to recover and I had pains in odd places for days afterwards. I must be getting old!
Of late, the front forks have started juddering, despite having several new sets of seals and one complete refurbishment. It makes the handling rather hairy once past 85mph, with lots of twitching and wallowing. Jamming on the front brake makes it feel like the forks are about to pop off. I am seriously thinking about fitting a whole front end off something rather more modern, although the large size of the Z’s front wheel makes this difficult.
I've tried various tyres on the beast. They all have one thing in common, if you try to ride with less than 2mm of tread the handling becomes very vicious. I rather like Michelins on the beast, they are cheap, last over 8000 miles and feel safe in the wet. Avons take second place with slightly poorer wear. A set of Metz’s lasted only 3500 miles - totally unacceptable.
The Z demands a decent O-ring chain and sprockets every 15000 miles. Running on a worn out chain wrecks what's left of the gear change, which was never exactly smooth even from new. I've adapted to it as the years have gone by.
The only part of the gearbox that has needed attention has been the clutch. New plates at 78000 miles, a whole new clutch unit at 157000 miles and another set of plates at 211000 miles. Even when new there’s always been a bit of drag, when it’s well worn it becomes very difficult to hold the beast steady at the lights when in first gear. Neutral is all but impossible to find and it has lately started slipping out of second and third gear.
The top end of the engine is tough but not so tough that it has survived 250000 miles without attention. Bores and pistons have lasted 75000 to 92000 miles, camchain and tensioner have been replaced three times and valve seals and guides go every 60000 miles or so. The valves are still original but have been reground once. Points are OK for about 30000 miles then have to be bodged for the next 10 to 15000 miles. I should have fitted electronic ignition but never got around to it - I quite enjoy mucking about with things that I can understand.
The ignition coils have burnt out twice, the first time causing erratic starting and poor running until they went completely. Most annoying to be rumbling along nicely, only to find you are suddenly riding along on a most constipated twin or triple. I had a merry time trying to find another cause of poor starting until the local Kawasaki mechanic pointed me in the right direction. The rubber inlet manifolds had hairline cracks in them. Too expensive to buy new, I had to scour the breakers for a good set. This problem occurred every 70000 miles or so.
Most of the electrical system is still original. Rear bulbs do blow once or twice a year, the handlebar switches have become very loose and I've never got more than 18 months out of a battery. The starter has had its bushes refurbished twice. The bike is easy enough to start on the kickstart, but with the endemic clutch drag in town it’s nice to have the electric boot to hand if the motor stalls in the middle of traffic.
The original headlamp wasn’t really good enough for fast riding but the quartz halogen unit I fitted solved that problem. Giving oncoming car drivers a blast of main beam has them scurrying for their dip switch. The horn was pretty pathetic as well, so I fitted twin air horns that make enough noise to make lumbering artics think twice about getting in my way. Or they did until a year ago when the vibes fractured their bracket, sending them tumbling down the road, never to be seen again.
A spate of blowing fuses, which left me stranded in fast flowing traffic, was traced to a corroded earth lead. The wiring has otherwise shown as little sign of losing its insulation as the tank and frame of throwing off their paint. I was most impressed with the standard of finish on the cycle parts. Although side panels that pulled off their spigots were not so amusing. The engine alloy needed a lot of attention to keep it from corroding. I ended up bead blasting most of it and polishing to a mirror finish. It’s now a weekly task to keep in shape.
The bike is very straightforward to work on. You can even take the head and barrels off without levering the engine out of the frame. The valve shims can be changed by any half competent home mechanic and even though the carbs are original and therefore now a bit finicky they can be set up in half an hour with a vacuum gauge set. There are not too many nice ones left, the basic reliability of the engine encouraged owners to radically tune the motor, which usually resulted in their falling off when the chassis threw a wobbler. Look for sensible chassis mods and a stock motor if you’re in the market to buy one.
I still use the big Z every day, it’s my only machine. With its polished looks it’s dead easy to pass the machine off as one of the new retro Kawasakis, although I would probably have trouble keeping up with the larger Zephyr. I’m pretty sure that someone who rode my machine would find it a bit of a dog, especially until I fix the front end (again), but to me we've been together for so long that I can’t conceive of life without the big bruiser.
Adrian Lawrence