Rolling from a factory in Akashi, Japan, as you read this, is the most exciting mass-produced motorcycle in the world. Kawasaki has built its Super4, a 900cc four-cylinder four stroke – the quickest, most sophisticated production bike ever built.

Two Wheels told you the news of this sensational machine back in June, correctly predicting configuration, large capacity and Kawasaki’s dramatic switch to a four stroke powerplant.

Designed to meet the highest standards required of a sports tourer, the Super4 develops a searing 82 horsepower, capable of powering the 506lb (dry) machine over the standing quarter in 12 seconds dead and to a top speed of more than 125mph.

Kawasaki has taken the plunge to a four-stroke multi powerplant in a unique capacity class, but the combination of design and capacity has produced a remarkably tractable high performance motorcycle.

The factory claims the Super4 to be practical for both high speed touring and sports performance (an understatement?), but it also offers a wide powerband that climbs smoothly from 2000 rpm to its 82 horsepower at 8500 rpm maximum – an honest 125 mph.

The engine is at its torquiest (54.3 ft/lb) at 7000 rpm. Although this is a lesser figure than that claimed by the 750 Mach IV (57 ft/lb), it is considerably more than the Honda 750 Four (44 ft/lb) and spread over a wide usable band. At 2500 rpm the Super4 has 36 ft/lb on tap.

Just what this means in terms of tractable road performance is very strongly demonstrated by the factory’s claim that the Super4 pulls cleanly in top gear from only eight mph – an innovation made even more surprising considering it comes from Kawasaki.

Oh sure, it’s a blaster, too – turned out by a crowd who are already acknowledged as kings of the tar-burners – but here is a dramatic step which broadens the high performance motorcycle’s appeal on the road.

The first drawings of the Super4 dated back to 1967, we were told by Mr T. Yamada, Kawasaki’s motorcycle division manager.

The following year a wooden mock-up was completed, at which stage the Super4 suffered the blow that nearly killed it and caused Kawasaki to hang back.

The blow was called the CB750. Honda pulled the wraps off the then revolutionary sportster at the ’68 Tokyo Motor Show and declared it ready for delivery.

It was, in many ways that count, quite different from Kawasaki’s pet project, but similar enough for Kawasaki to pull out for a re­evaluation. It was still a question of one four-stroke, four-cylinder aceing another, however you looked at it.

But the way the hungry world market gobbled up the CB750 convinced the two-stroke specialists the market for an alternative 4/4 (cylinders and strokes) was still attractive.

The first dohc powerplant of 900cc in four-cylinder, four-stroke design is of compact design, sufficiently so to allow the Super4 an overall width of only 31.5 in. (The Mach IV is 33.5 in. wide and the CB750 measures 34.5 in.).

The cylinder design is 66mm square – a desirable characteristic for smooth, high revs – and needle bearings are used on both the big ends and crankshaft mains.

All parts can be removed (except the crankshaft itself and parts of the five-speed transmission) with the engine in the frame. Periodic adjustment of valve clearance shims in the dohc can be done with the camshafts still in the cylinder head.

And there’s a new constant flow lubrication system for the chain, too. Kawasaki have equipped the Super4 with an automatic pressurised system pumping oil at a rate synchronised to the bike’s speed.

Overall powerplant design shows a noticeable leaning to anti­pollution features, and the Super4 has obviously been designed to meet possible future legislation in this area. The motor uses sintered valve seats and Kawasaki claims it can be run on lead-free petrol without loss of performance.

This means that the motor (and valves particularly) will operate without the pollution-producing lubricants which are found added to petrol but which will have to go if stringent anti-pollution measures become law.

A Positive Crankcase Ventilation system (PCV) recirculates blow-by gas from the wet-sumped crankcase, and the system is said to offer a dramatic reduction in hydro-carbon emissions.

The Super4 five-speed constant mesh gearbox has obviously been neatly matched to the motor’s wide torque spread to stress the big­boomer’s touring potential. At say, 70 mph in top (fifth) you’re cruising at comfortable speed and engine speed is 4500 rpm.

The Super4 not only goes, it stops. The disc/drum combination (same as the Mach IV) hauls the bike to a standstill from 23 mph (50 kph) in 36 ft. An interesting figure this one. Our test Mach IV (May issue) stopped comfortably in less than factory figures but we’ve tried private bikes since and experienced a variation of 10 ft! Obviously, one of the critical areas of the Super4 is going to be the way it’s tyred!

The factory reportedly experimented with 10 variations of frame design for the final product, and prototype test riders have said the bike handles low-speed manoeuvres easily and offers stability in both heavy traffic ancl touring conditions.

The Super4 has an all-new instrument panel, too. The easily-read tacho/speedo dials are now separated by an instrument panel, on which the key keeps company with neutral, flasher, high beam and oil pressure warning lights.

“The Kawasaki Super4 is our expression of confidence in the future of high-performance motorcycles,” Mr Yamada said.

You know, we like that phrase, and if the Super4 is as good as the Mach IV it could be a new high in the art of building bikes. In fulfilling this aim Kawasaki have created a whole new market. The Super Sports Tourer has arrived!

Two Wheels. November, 1972

Secrets of the Super4

Being the first to 130 mph is only part of the story. Kawasaki’s boulevard brute is a long-distance wrist twist that gets it all together. Built to eat the miles in slow-revving, fast-moving perfection, it’s impossible to know properly in anything shorter than an interstate dash. We needed 1000 miles, but snatched a quick few hundred for this first local impression.

The Big K is the fastest production bike capable of registration in Australia.

It pulls from 120 like an average 750 pulls from 90mph, yet its smooth, flexible power is a package that spells out effortless long­distance high-speed touring in unprecedented style.

There’s still not a lot of Super4s around – they’re not a mass-transport machine – and we were fortunate to get a bike for an early local test from Melbourne’s Peter Stevens organisation.

Our test bike was destined for a fascinating future. It had just been run in by Bill Crawford to take its place in the Peter Stevens Team Kawasaki production racing lineup.

Bill kept the revs to 2000-4000 for the first few hundred miles and then opened up to 6500 rpm until 1000 miles were on the clock. We picked up the bike with 1600 miles behind it including a few hundred miles of having been revved out to maximum before a thorough check and service.

In the short time Peter Stevens has been handling the Super4s two small faults have become commonplace with most of the bikes – minor oil seepage from the cylinder and head gaskets and the loosening of the camshaft sprockets. While a few dribbles of lubricant mean nothing more than an eyesore, the sprocket trouble requires immediate attention.

A single row chain from the centre of the crank drives to sprockets on both cams. As the miles are built up the bolts tend to loosen and allow the sprocket to rattle. Rectifying the trouble is no more involved than removing the two cam covers and each bolt in turn and coating them with a locking compound.

Our test bike had the job done with the remainder of the Peter Stevens stock when new and the subsequent checking at 1600 miles showed both sprockets to be tight.

After the few hundred miles of our test we were left with the impression that the powerplant was faultless, but not so every component. With 82 bhp going through 530 lb a great deal of strain is put on to the transmission. While the chain is huge and, like the rear tyre, can be quickly replaced, the clutch and gearbox have to put up with untold punishment, supposedly for the life of the bike.

It’s interesting to note that the clutch was the one component that was altered after evaluation of the prototype in America. After exhaustive testing (including a 122mph average long- distance test) the rivets holding the clutch housing to the gear drive began to fail. As a result of this a new, more robust design was employed.

The multi-disc wet clutch itself is immense, as is suggested by the diameter of the outer cover, and engine shock loads are cushioned by radially positioned springs in the clutch hub.

Under hard acceleration from a standing start (and not breaking away the rear tyre) the clutch produced some horrible vibrations and noises as the slip was taken up under power. The gearbox also showed a weakness under acceleration when at maximum revs (82 bhp remember) there was a distinct tendency for the box to jump out of gear.

We emphasise that this was right on the limit, and that means riding the bike much faster than is normally possible for road use.

Staying legal (in most States) requires no more than a few thousand revs in each gear, which with the evenly spread ratios means roughly 20, 30, 40, 55 and 65 mph at around 3000 rpm. Though maximum power is developed at eight-five the punch at one third of this is more than sufficient to handle the 500 lb weight effortlessly.

So flexible is the power that the bike can be walked down to 12 mph in top gear and instant – yes, instant — acceleration is available at the flick of the wrist. In no way is the 900 a revver, it is just that the revs are there should you be man enough to try them.

With the flexibility of power comes the versatility of the handling. A 130 mph projectile has to have nothing short of excellent handling, which often results in sluggish low speed manoeuvrability. To our astonishment the big 89-inch wheelbase Kawasaki is not only rock steady at the top end but is incredibly light on the handlebars around town. Between our 130 mph speed runs the bike was brought to a halt and swung around in a U-turn made easily without footing on a 10 foot circle.

This degree of perfection in handling is very much a first, as previously the best high speed 750 (Ducati) proved a handful through traffic, and the most manageable 750 (Suzuki) turned out to be unstable at over the 100 mph mark.

Kawasaki’s Super4 frame has been the subject of intensive development, and its centre of gravity, wheelbase, and all-round geometry exist in a state of great compatibility, regardless of motor size, although, as we said in our November preview, actual motor dimensions are not extreme).

An example of this is the close proximity of the gearbox drive and swing arm pivot point. The closer the proximity, the smaller the chain arc prescribed during suspension movement and subsequently, there’s less “unnatural”. chain movement and wear.

Quite obviously, chain wear is going to be terribly important to the Super4. The handbook and notices under the seat warn that the rear tyre and chain should not be used for more than 5000 miles and that the maker is not responsible for the consequences of usage greater than that. But the Big K is strictly for the man who is willing to pay for this kind of motorcycle.

The factory has actually done much to preserve the chain with a separate oiling pump which has its own supply tank under the left hand panel and delivers a factory-­rated flow of 5 cc per hour at 1500 rpm.

Incidentally, when we did lift up the seat we were surprised and pleased to find the complete technical specs (including a wiring diagram) attached underneath.

In a nutshell, much of the Kawasaki is a whole new experience, made up of a multitude of happenings. The bike is incredibly quiet. It’s rated at 83-84 decibels which (rather oddly) means you can’t hear it. That’s the smallest of the factory-published ratings we’ve read.

And (perhaps this comes under “noise”) the bike doesn’t ground and grind. At all. That’s probably just as well because the machine has a one-piece header pipe/muffler which promises to be expensive.

All four pipes need to come off to remove the rear wheel and although there’s few bolts it’s a fidgety job and took about 30 minutes first time, although we think 20 would be realistic.

We mentioned in our preview the powerplant’s factory-boasted accessibility (a top end teardown without taking the motor from the frame) but with a complete workshop manual available on the machine we were able to probe some of the most interesting internal features.

The Super4 has the very desirable square bore/stroke ratio (66 x 66 m) and the mechanics at Peter Stevens were enthusiastic about the powerplant’s state of balance.

Built around a six-bearing crankshaft, the firing order (left to right when viewed from riding position) is 1-2-4-3. The two outside pistons rise and fall together, alternating with the two inside pistons which are also in unison.

This produces a self-cancelling reciprocation (each pair of pistons are always going in opposite directions) and a power impulse every 180 deg of crank rotation.

The crankcase splits horizontally, but the shaft is a built-up (not one-piece) component with a reported life expectancy well in excess of 50,000 miles. The bearing layout is caged roller mains, caged roller rod big ends and full-floating piston pins.

One of the crank’s interesting characteristics is that the primary gear drive lies between cylinders 3 and 4 and is machined right on the crankshaft.

So how does all the sophistication rate in one, large, 903 cc package?

Well, despite its size the clutch is an easy pull. That says something else good for design. So does the fact that this is one of the easiest multis you’ll find to change plugs on. All four plugs are easily accessible from their respective sides of the machine.

Valve adjustment is a slightly different matter, hence our 45 min time estimate. It’s made by adding or removing shims (calibrated in hundredths of a millimetre) from between the valve spring cup and cam lobe. It sounds fairly complicated, but the components are all exposed with the removal of the one-piece valve cover.

Okay, you’ve read our preview, and now our first experience. You know everything we do. But we have a feeling there’s a lot more to learn about the Super4. It’s one of those bikes you just keep on discovering.

Foremost in all our minds – yes, everyone had a ride – was a sensation that you were riding what the drag racing fraternity would call the “Top Eliminator”.

You pull away from the rest without any conscious realisation that you’re actually winding it out.

But that’s not what the 900’s best at – or even what it’s built for. It’s redlined at 10, with top horses available at 8500. But this machine loafs along at 5000 rpm at speeds which could realistically be considered a maximum on Australian roads.

You “ghost” along on a silent, almost magic, power source.

And something else. The coming of the Super4 has made us glad we’re a country of wide, open spaces!

By Derek Pickard. Two Wheels, April 1973

Big Mutha…Still a Big Mover!

KAWASAKI’s Z900 has further compounded the problems of the original Z1 posed for all makers of big-bore machinery: What do we do now? For this must be a question asked in one way or another by a high-up in every factory which produces a big blaster.

And it was asked at Kawasaki. That’s probably why the Z900 is an improved, more civilised and refined bike in many ways. Its performance has also changed slightly, but it’s still the only bike we’ve ridden which comes close to being all things to all riders.

First off, it’s tame, so tame that at first you tend to go off the deep end praising the thing for its low speed stability (steady as Ayers Rock – the monolith not the rock group) and completely usable low speed urge. For example, the bike is running at 3000 rpm at 80 km/h in top (fifth) gear — smooth, with all the power in the world on tap. Unreal.

And in the first 1000 km, the handling/ride/suspension seemed damned good. Tight high-frequency ripples would have the front forks chattering, but that was it. Those sneaky six centimetre recessed manhole covers hit at speed wouldn’t faze the forks. A quick twitch after a bit of slip across the metal cover and that was it … No fuss, no drama. Great.

So it can be ridden at a fair clip through corners, and at slow speed through traffic, it’s comfortable and above all, it’s easy to ride. A brilliant bike, right? Not quite, but close, oh so close. You see the running-in distance was covered keeping the extremely under-stressed engine below 4000 rpm (the redline’s at 9000), with occasional quick surges slightly above that.

We’re firm believers in breaking-in an engine by feel rather than arbitrary engine rev limita­tions, but even so, up to 4000 rpm was the norm for city riding and (legal) highway jaunts. Until about 4500-5000 rpm the mill is smooth in the way of a big well-balanced and tuned transverse four; you can feel slight tremors of power, but nothing that remotely affects comfort.

Above that, on our second test bike anyway, things roughened up a bit – again not quite enough to affect comfort (and I tried riding for almost 12 hours straight with only petrol/milkshake/cigarette breaks), but enough to blur the mirrors and generally make the rider aware the engine was starting to work that little bit harder. We might mention here that the first test bike’s engine was smoother than the second, as have been all but two of the dozen or so 900s we’ve ridden.

Kawasaki’s service chief Dave Pinnington, kept in touch with us during the early stages of the test as the vibes had him a bit worried at first, but as the engine loosened up, the vibes decreased anyway and we didn’t consider them to be in any way detrimental to rider comfort, performance or the general well-being of the bike.

The Z900 is the first 900 model that has had any real major updates and the obligatory changes apparently just for the sake of change since the Zl was introduced in 1972. The Z1B had all sorts of brilliant updates … Like a little sign which read “Kickstarter” beside the, you guessed it, kickstarter, little tags telling you what the helmet hooks were and other generally sensible changes (Yeesh!).

But the Z900 is a whole new scene. Okay, there’s not been any big changes – no beefed-up frame or improved swing arm bearings or major internal engine work – but Kawasaki has paid heed to most of the more annoying criticisms the early models aroused.

Like the seat. It was always okay for hanging your bum off the side during the big early Sunday morning play races, but travel any big distance and the rounded edges right up front would start splaying your cheeks. It was pretty uncomfortable after more than a couple of hours on the move.

The new seat is great; it’s wider and has more squared off edges up front, for better, more even support over long distances. And you can still hang off the side in play-races. It’s not a BMW beater, but it is good.

Next improvement, and another big plus, is the new dual disc set-up up front. They’re two millimetres thinner than the old single disc, but they still add their bit to a weight hike of 8 kg over the Z1B. And the discs and calipers are unsprung weight, which makes the forks work that much harder.

Anyway, the brakes themselves are excellent, with plenty of feel and good stopping without undue drama. And they work in the wet with standard pads, unlike the early models. One thing surprised us about the discs themselves though: They rusted on the edges after about nine days. Very odd! And when you consider that the Japanese use stainless steel for their discs purely for appearance sake, rather than have rusty but super-efficient steel discs like the European bikes, you wonder even more!

The discs also scored fairly heavily in a short time, but that’s as much a reflection on our performance and braking tests and the high-speed big trips as anything else.

But back on the track. The Z900 has some of the best braking around, Suzuki water bottles, Laverda 1000s and all, despite the bike’s mass. It stops fast and feels stable and perfectly controllable, which is a lot more than just nice to have.

Then there are the new rear units. More damping, a slight increase in travel, a little tauter springs – good stuff which stops the back end wallowing and eases the sponginess of the old units. How long they’ll last is another question though, as Z1 units have never had what it takes to handle all of the weight. Replacements are still on the needed list, but the need isn’t anywhere near as urgent as on earlier models.

Next on the change list is the carburetion; down to 26 mm Mikunis from 28 mm on the earlier models. They’re one of the things that slightly altered the power characteristics of the bike. The other is the muffling, which, as is readily apparent from the dyno report, is designed specifically to meet noise requirements at certain running speeds, which just happen to be around the legal road speeds in most countries.

But the smaller carbs and increased muffling haven’t detracted from the big Z’s road performance. In fact we’d be very interested to see what sort of times Gregg Hansford could put in around Amaroo Park on one. It is a fraction slower at the top end, but it’s still quicker than just about anything else around (barring 900 SS Dukes and Guzzi S3s) at above 160 km/h speeds. But the improvements in braking, stability during cornering and its ability to accept anything but desperate line­changing on poorly surfaced or very tight corners, could make it a faster bike around a track like Amaroo.

In actual road performance, the altered intake and exhaust systems (including, we believe, some minor flow work on the head) simply mean a bike which always had a lot of low-speed grunt now has an exceptional amount. And it’s the engine of the bike that really grabs us. It’s quite simply the easiest-to-use four there is amongst the big bores because of its spread of usable power. From idle to redline the engine performs beautifully.

As we’ve said, weight is up eight kilograms, mainly due to the dual disc system, the larger rear mudguard and tail-light assembly and other new bits. This has the unfortunate effect of pushing a suspension system which is already taxed by the weight (236 kg) it carries, that bit farther away from being anything more than good.

We believe, as would any rider, that changes like a locking fuel cap, hazard warning lights (all blinkers flash at once), a buzzer on the blinkers and a bigger tail-light won’t sell Kawasaki any more bikes.

But if the cost of the unnecessary improvements was put into closer tolerances in fork sliders, or research into strong wheels, or better methods of rear suspension, then the bike could perform better and more people would buy it.

But as it stands the Z900 is the best all-round performing big bike we’ve ridden this year. There are one or two which could have more appeal in certain ways, but they’re specialised performers, while the Z is at home anywhere — high-speed cruising, blasting or slow speed city work, it’s very good at them all.

The bike shares the same redesigned engine kill switch button and combination headlight flasher/horn with the KH250 Kawa (Two Wheels, March, ’76). It’s a well-thought-out design which operates faultlessly, as do all the switches. But that indicator beeper! Okay, people sometime forget to turn blinkers off and it can be dangerous. But the thing is so annoying! Not only does it sound like a cross between a demented, castrated frog and a small cricket, it alters pitch, squawks and screeks and has pedestrians turning around in amazement metres away. Owners who wish to stay sane will disconnect it or alter its sound.

Australia also scored the long rear mudguard and strap across the seat models, which is a pity in a way as the long guard destroys the Z’s lines and the strap is the only mild annoyance on an otherwise excellent seat. In fairness to people who take practicality into account on a blaster, the longer rear guard is probably more efficient in the wet.

While we’re at the back of the bike, the Z now has a big squarish tail light like the KZ400’s and the ducktail shape has been altered very slightly to accommodate it. The paint work on both the bikes we tested, one brown and one green, was blemish free and apart from the joins on the pinstripe tapes being visible, finish was faultless (frame welds excepted, of course).

The sidecovers have also been redesigned to accommodate the new air box/filter arrangement, which further reduces intake noise. Another incidental change as a result of the cylindrical air filter and the dropping of the chain oil reservoir is that there’s more room under the seat. Even the tools are easy to fit into their holder, which is more than can be said for most bikes.

The last on the list of changes alters from State to State. Some official – obviously not a bike rider – in the NSW Department of Motor Transport decided the bikes had to have flat mirrors, so out went the neat-looking black mounted mirrors and on went cheap chromed ones that vibrate worse than the factory ones. So not only is the field of rearward vision decreased, it’s also not as usable over the rev range.

Despite arguments to the contrary, a look in the mirror at a stationary object and then a glance over your shoulder is enough for any person who should have a licence to safely assess distortion. And any rider who doesn’t have the odd peek over each shoulder – especially when changing lanes – shouldn’t be a rider and probably won’t be one for long.

Forget the changes and you’ve got the same old Z1. The engine is the same dohc four, with the cams driven by a chain tensioned by a stack of rollers and operating between the centre two cylinders. The cam lobes run directly on cylindrical followers which in turn sit on shims which are used to adjust valve clearances. This is the only hassle about working on the engine. We’ve yet to meet a mechanic who actually likes doing valves on a 900. It’s time consuming and fiddly, but on the other hand, it works well in terms of performance and as it’s a small hassle, we’ll take performance!

And you get that performance in heaps. Because there aren’t any rocker arms, the 900 is a free revver with a 9000rpm redline — more if you’re keen and do a bit of simple head work like bigger exhaust and inlet valves and some port flowing.

The valves are small, especially the exhausts, and the cams are very mild. With the small carbs and restrictive exhausts, the Z900 engine is breathing at about 50 percent of its ability, but because of the sheer grunt from the big capacity, it’s vastly under-stressed while still churning out more torque and kilowatts than any other standard road bike.

Compression ratio is still 8.5:1 and the PCV system is still there. It consists of an air and oil separator at the top of the crankcase which vents combustion vapours to a plenum chamber, to the air filter and back to the engine to be re-burned. It’s a simple and effective pollution control method which reduces hydrocarbons by about 30 percent.

The light, one-piece conrods are super-strong and the pistons ride on needle roller bearings. The crank­shaft is a pressed-together unit supported on four main roller bearings. The engine/transmission oil circulates through a filter and to the engine by a gear-type pump. Because of all the needle and roller bearings, oil pressure is low – around 41 kPa (6 psi). A total of 3.7 litres of oil is carried in the low, wide sump (to keep engine height down). No dipstick is necessary as there’s a sight glass on the clutch cover. Cam chain adjustment is a matter of getting two pistons at tdc and loosening and then tightening a bolt and locknut under the carbs. Like everything about the Z900 engine, it’s mechanically simple and efficient.

When we first picked up the Z900 from Kawasaki, the first static impression was size, mainly due to the high, wide cowboy handlebars. Out of the workshop and on the way back to the office it was the heavy, clunky gearchange.

Is it a dog? That was the first question. Is it one of those bikes that just get put together slackly, on the day after a holiday or something? It was tight, like any other new bike, but it was also big, and though quite controllable in traffic, it didn’t seem to have the reflexes for survival.

The impression was wrong of course, as during the next phase of the test we became quite accustomed to the bike and enjoyed its “chuckability” which we became familiar with as we put some distance up. Then the harder we pushed, the more faults showed up. Not faults which detracted from the bike unduly, but little things, mainly results of manufacturing expediency as practised by the Japanese which kept the Z900 short of perfection.

When we first picked up the Z, it had a little more than 100 km on the odometer and the Japanese K87s were very much new … and slippery, as a few lurid slides showed. As the tyres wore in they were surprisingly good all-round, particularly regarding wear, but were a little too hard around the shoulders – not good in the wet. In the dry, when riding the shoulders with the centrestand just scraping, things got pretty squirrelly too.

The Z’s good manners handled it okay, but better tyres, like Dunlop Red Arrows, would be called for by any serious owner, though the better the ancillaries get, the more weaknesses will become apparent in the frame/swingarm/front forks department.

After two days tooling around the city and suburbs, we set out specifically to free up the engine in preparation for a long blast. As the big mill felt happy at 4000 rpm (a road speed of 100 km/h), an all-day run down the coast from Sydney, taking in some of the nice windy parts and for the rest just cruising at the speed limit through the pollution of Wollongong and Port Kembla, seemed like a good idea.

Tell the guy at the gates to the Royal National Park I’m just passing through and he smiles and waves. Either the Z900 and I looked respectable, or the guy was a rider and knew about the park! Then down the winding hill to the causeway behind some cars. Around them up the other side, then start pushing a bit, but still keeping the newness in mind.

A patch of gravel and dirt (common in the park) puts things out of line for a moment, no more, and everything’s in hand before the heart even gets a chance to receive its adrenalin ration. A bit of a slow-down while that one is pondered: An instinctive reaction to a quick slide at about seven-tenths through a smooth corner gives a fast reaction with no drama. Good manners.

Speeds pick up and bumpier, tighter corners are met. A bit of skittering around the back, the weight shows up, and a bit of muscle is called for in tighter going. Then, a particularly memorable corner: decreasing radius, three centimetre-high ripples all around and a six-centimetre-wide gully type depression in the middle. Aaaaagh! The frame’s hinged in the middle!

A big wallowing lurch, followed by a kick from the handlebars, a screech from the heavily grounded centrestand and then up straight as the corner ends. It’s a bit of a roughy when pushed hard, then. But it can be controlled pretty easily, providing there’s no panic and a bit of muscle is used to keep everything honest.

For the rest of the day, in which 750-odd kilometres were covered (at an average of 230 km a tankful) the Z900 showed itself to us as one of the best average speed cruisers around. It spent most of its time in fifth gear because of the power available all the way up to the engine’s tight period (which by the end of the day was up to 6500 rpm, though it was rarely taken that high because the first service was then overdue, as the dirty jet black oil testified) and was a safe and forgiving, if less than top quality handler.

But it went very quickly for the conditions, even when using half the engine’s available power. How would it go when pushed hard over a big distance? We thought even then it would come out well.

Why? Mainly because of the state I was in at the end of the break-in day. Sitting in the lounge at home I ticked off the things you’re usually acutely aware of at the end of a long ride: Neck, okay, but then I wasn’t straining into a 180 km/h air blast for the trip, only one of 100 km/h; shoulders and arms a bit sore, the result of buffeting from those bloody cowboy bars; back, no damage; bum, no damage; legs, no damage. Hmmm. Then, as the refreshments are picked up I become aware of my sorely mis-shapen hands, of rows of those half-callus, half-blisters, of red, sore palms and stiff fingers. I write “handlebar grips(!)” on the notepad and underline it heavily.

Later I discovered they weren’t as diabolical as I’d first thought. It was mainly the fault of the bars and the heavy hang-on they caused. The stock bars were great in the city, giving plenty of leverage and allowing the rider to sit up straight and keep a high lookout for madmen in cars. But they’re on the bike for the showroom sell, to make it patently obvious that yessir, this is the mutha Kawasaki, this is the big one baby, and unless there happens to be a GL1000 or a Harley parked alongside, people who are influenced by size will snap up the Z and its showroom cowboy bars.

After the break-in, at the first service, Kawasaki agreed to remove the stock bars and replace them with “Six-Hour” bars (slightly raised, about five centimetres higher than flat bars) which would have been just about perfect for the stock bike. Unfortunately, none were available, so flat bars were fitted. A mite too low for city work, but still comfortable, the flat bars were perfect for Sunday play races and still allowed enough leverage to keep everything under control on dirt roads or around city traffic.

But during the ride to Melbourne, by the time the outer suburbs were appearing, it was plain the bars were a little too low for high-speed cruising, though with a fairing they would have been okay. The angle of lean wasn’t quite perfect – the neck had to be bent slightly and this really told heavily after nine hours’ straight riding.

But I’m getting ahead of myself. During the running-in 1000 km, nothing went wrong with the Z900. The gearchange loosened up a bit, though it was still stiffer than any other 900 we’ve ridden, the drive chain only needed adjustment once and the bike was comfortable, responsive, forgiving and quick. 

I decided to use the Hume Highway to Melbourne, thinking that though there are longer but faster routes with better road surfaces, the Hume is the shortest in actual kilometres. I was told tales of endless radar in NSW and relentless police in lurid Falcon GTs in Victoria, but I didn’t see one police car on the trip down. And I was looking hard!

On the other hand, I saw plenty on the way back and was pulled up twice for licence/registration/defect checks, which I was assured by the first earnest constable at Albury, were necessary to prove to superiors that he was doing something during his shift! Who said not enough was done in terms of real road safety by the various authorities?

Preparation for the ride was minimal. The bike was serviced and the flat bars fitted and the things that always go wrong on trips – spokes, chain, cables, various nuts and bolts -were checked and that was it for the bike.

A change of clothing (spare teeshirt, jeans and jocks) was at the bottom of a small rucksack which also contained a light showerproof ski suit, a pair of nylon wet weather pants, a Line 7 weatherproof jacket, a pair of thick gauntlets and a superb Soubirac snowmobile racing suit from France which usually hangs like a red suit of armour in the Two Wheels office. Also included were a can of Finilec, a can of chain lube, two plugs, some wire and various tools.

Deceived by a warm, sunny Sydney afternoon, I set off at about 4pm clad in boots, jeans, sweater and leather jacket. The rain hit near Mittagong and looked like it would dog me for the entire trip, but it was gone by Goulburn. The bike didn’t mind the rain and enabled me to keep a high average speed for that section very safely. Not so a guy on a GL1000 I rode with for a while! It was slipping around badly and the rider simply had to take it very easy. The Z900 kept forging on.

At Gundagai, which was the target to be reached by sundown, I looked at the notes on petrol. The previous weekend I’d been getting 230 km a tankful, and once 270 km, but so far the best I’d managed was 210 km. But then, the bike was still pretty tight and I thought in time the range would improve, as it eventually did, when on a one-day blast I covered 290 km.

The only problems encountered so far were the centrestand grounding on wild right-handers and the footpeg just touching on the left. These aren’t so much problems in themselves, but the bike’s antics were!

Everything on the bike was okay — chain, wheels, frame, swingarm, forks — but the Z was getting too skittery too early. Admittedly that was at a good speed — double the advisory signs then add according to how far you could see around the corner — but it didn’t feel right.

At the next petrol stop I checked the tyres pressures. Way too high! And the shocks were on the stiffest of the five settings (left there after the mid-week experiments), so they went back to the number three setting.

No sweat after that. Okay, it’s a long way from being a surefooted Italian, but it’s still good – at least on par with the best of Japan’s new “handling” European market bikes.

Also, the gearchange, which started off heavy and clunky and had been improving gradually, suddenly left the consciousness altogether. When it was next noticed it was silky smooth but with precise shifting, clutch or no clutch. In fact the clutch/gearchange became one of the joys of riding the Z900 for us, using effortless, smooth, clutchless downshifts and flat changes … faultless.

Riding down the Hume to Melbourne is a good trip. The road out of Sydney is bumpy and has bad corners. The surface also ranges from downright slippery to patches of good, grippy bitumen to potholes, ripples and rough edges. It’s not nice.

But you start off fresh and alert for the bad bits and as you get tired the road improves, particularly when in Victoria, where wide, flat, well-surfaced roads take most of the danger out of high-speed cruising.

At the first meal break, at Wangaratta in Victoria, I was once again surprised by the drive chain. It didn’t need adjusting. I sprayed it with gunk muttering under my breath about the amount of maintenance that went into a 900 I once owned, the first model, with the little elastic chain.

And then there was the problem with the headlight. I wanted to get the bad bits over in natural light, mainly because a few weeknight excursions had left doubts about its value, particularly on high beam. I expected it to be dim, but then it started flickering on high beam, usually when shutting down after sitting on 190 km/h for long stretches. And what is it you shut down for? Corners you can’t see very well, little animal shapes in the distance or the sudden appearance of road works. After a few hairy moments it was stop, check the wiring connections and poke around. Nothing. Was the high-speed running overcharging? Only thing was to press on, put the headlight on low beam and push the shell up a bit for a wider beam.

Even without the headlight problems we’d have recommended fitting a replacement quartz halogen unit or an auxiliary riding light. For the night cruising speeds within the Z900’s capability, the standard lighting system is not adequate and is the next thing Kawasaki should look at. BMW and Guzzi can fit great halogen units to their blasters, so why not Kawasaki?

On the plus side, the instruments are superb, particularly at night. The speedo and tach are well illuminated and readable at a glance. The high beam warning light, with the oil, neutral and stop lamp warning lights, sits in a rectangular block between the instruments, with separate left and right indicator signal lights below, on each side of the ignition switch. All work well – none are too bright at night or not bright enough during the day. The ideal compromise.

The switches are well placed, fall easily to hand and all operate smoothly and distinctly. The weakest is the high/low beam switch which requires some wrist distortion to operate, but with the present layout which is so good, there’s no alternative position.

Predictably, the horn isn’t loud enough. This is another area the European manufacturers don’t ignore – witness the big dual horns on the Laverda Jota 1000 – but the Japanese persistently give us equipment which is simply not good enough considering intended use and performance capabilities.

Might as well get the last bit of bitching done. That’s the toolkit. Better than most other Japanese bikes? Definitely. Adequate? Only just, and then only until the spanners (and those crummy pliers) distort and the nuts and bolts on the bike are damaged. The metal’s too soft and they can end up costing you more than the price of a good toolkit in the long run.

Apart from confirming the Z900’s high speed cruising capabilities, the trip down to Melbourne confirmed my first· impression of the bike from the test we’d given it the previous week. And its reliability, apart from the head­light.

The trip back was to be more of a severe test, as it turned out not so much of the bike, but the rider! The best part was there was no rain, all the way back to Sydney, which is a pretty rare thing.

Melbourne was left behind at about 6 pm on a warm, cloudy Sunday evening, with a bleary-eyed rider determined to make good time, to get back to the comforts of his own bed and then get into the week’s work.

But it’s not a good run from Melbourne to Sydney, for the same reasons it’s better going the other way — the deterioration of the roads the farther into NSW you get and the downright bad conditions around Sydney. Add to this a headlight which was now starting to flicker on low beam (high was gone altogether), cold, billions of giant bugs and a super-stiff neck and you can understand how I felt when I rolled into the boss’s yard at 5.30 on Monday morning to leave a note under his windscreen, saying I’d come in if I woke…

And the trucks! Wow, do those things make life interesting! The truckies give bike riders a fair go, and if you’re travelling fast with longish stops for petrol you see the same ones quite often.

One of my truckie “friends” gave me a bit of a turn. About halfway down a long hill, sitting on 160km/h, I noticed a set of lights appear over the crest behind me. Being naturally cautious, I throttled down to 130km/h until I could see what it was.

But I didn’t get a chance. The big mutha blew by with a good 50km/h on me! Shock! Disbelief! After bobbing around in his wake for a while I turned it on a bit and kept the truck in sight, all the time thinking “No, no this isn’t right. I can’t be sitting on 160-180 km/h trying to catch a giant truck. It doesn’t happen!”

I got him halfway up a long climb and pulled out to overtake him (he had signalled with his blinkers it was clear). When level with the cab I waved and looked up to see this young guy sitting in the cab cracking up, laughing and banging the wheel of the big monster. He waved and I went on, wondering how many bike riders he’s blown out with his game…

And that was the trip. The bike was in perfect condition front to back, though it was living under a pile of dead bugs and 3000 km of road grime. Tyre wear wasn’t pronounced and mechanically nothing had gone wrong or looked like going wrong, apart from the headlight. The exhaust pipes had started turning a light straw colour on the two left cylinders and the outside right pipe was just starting to go. The bike also desperately needed another service and oil change but was performing better and better with every kilometre, though the high-speed handling had stayed static as we learned the bike properly and the shocks and forks wore in.

In fact the Z900 impressed us as much as the original Z1 did when we first rode it. It is as applicable to conditions in the bike world now as the Z1 was then. There is no other big bike like it for all-round suitability. High or low speed cruising, city traffic, play racing, production racing, it does them all well.

And though there are better bikes around in specialised areas, we must simply say the Z900 is the best all-round sports tourer you can buy, particularly when cost, the final argument, comes in so heavily in favour of what you get.

By Jeff Brown. Two Wheels, June 1976

Falloon: The Classic View

As the Baby Boomers hit their 60s they are redefining the parameters of collectable motorcycles. Whereas until recently the staple classic bike was a 1960s British parallel twin, the goalposts have now moved to the next decade.

This decade really began in 1969, a pivotal year for motorcycling. Honda released their landmark CB750 four and Kawasaki the potent Mach III triple (AKA “The Rocket with a Sprocket”). Britain tried their best with the Triumph/BSA triple but this was merely a last ditch stand before eventual obliteration. For Kawasaki, the two-stroke Kawasaki Mach III set new performance standards, but provided limited comfort, was excessively thirsty, and outside the mainstream of motorcycle design. Even before the Mach III’s release Kawasaki was working on a new four-stroke 750 four, but when Honda unveiled their CB750 in October 1968 they were forced to take timeout for a rethink.

Rather than scrap their existing 750cc N600 project, Kawasaki decided to upstage Honda. They increased the displacement and included several features previously the reserve of exotic cars or racing motorcycles. The transverse four-cylinder four-stroke engine had square dimensions (66×66 mm bore and stroke) and displaced 903 cc. Although the engine tune was very mild, with an 8.5:1 compression ratio, 36 and 30 mm valves, and four Mikuni VM28 mm carburettors, features such as double overhead camshafts and a 9-piece pressed together roller bearing crankshaft set the Z1 apart from the competition. The crankshaft was supported by six main bearings, with one-piece con-rods. The primary drive was by straight-cut gears, the drive cut directly into the flange of the number four crank counterweight. This resulted in a compact and direct primary drive system that minimised drive train snatch. Although the pressed-up crankshaft was an expensive solution, it was incredibly strong, and when welded together could handle enormous power outputs.

Endeavouring to quell any criticism of low quality and cheapness that had blighted some earlier Japanese products, Japanese motorcycles of this era were seriously over- engineered. But even compared to others the Z1 took robustness to a new level.

Anticipating future environmental controls, sintered alloy exhaust valve seats allowed the use of lead-free fuel, and a positive crankcase ventilation system with an air/oil separator on top of the crankcase was incorporated above the gearbox. With an environmentally quiet (84 decibel) four-muffler exhaust system, the power was 82 horsepower at 8500 rpm. The Z1 was unquestionably the most powerful production motorcycle available when it was released at the end of 1972.

While the engine specification set a new standard for production motorcycles, the chassis was more conventional. The double cradle frame was inspired by Norton’s Featherbed and constructed of mild steel. The suspension was also unremarkable, with a 36mm Kayaba front fork and typical under damped Kayaba twin shock absorbers.

The braking was also marginal considering the power, but the 296mm stainless steel single front disc with floating caliper was state of the art for the day. With Dunlop K103 and K87 Mk II tyres, specifically designed for the Z1, handling was acceptable but not outstanding. The early 1970s was an era where engines dominated the chassis, particularly with Japanese bikes, and sometimes-loose handling was the norm.

Dry weight was a considerable 230 kg, but nothing else at the time could match its engine performance. Period roadtests posted standing 400 metre times in the low 12 seconds with terminal speeds of above 180 km/h, and a 210 km/h top speed.

Considering all Z1s came with an upright riding position and a high, wide handlebar, this was impressive. This combination of performance with general ease of use, electric start and overall reliability, put an even larger nail in the coffin of British motorcycling than Honda had managed with the CB750. Distinguished by a black highlighted engine and “Jaffa” black and orange colours, thousands of Z1s were sold in 1973. Ordinary people, who just happened to like terribly fast motorcycles, rode them on the street.

Production numbered more than 80,000 units during 1973 and 1974 and the Z1 was well on its way to becoming Kawasaki’s most successful model. Production couldn’t meet demand and with most destined for America Z1s were in short supply in Australia.

The Z1 became the similar Z1A in 1974, changes largely limited to colours and the natural alloy silver engine finish. For 1975 the Z1B lost the automatic chain oiler, the front forks received revised dampers and softer springs, and to improve low speed running the automatic ignition advance was revised. It was a downhill slide after that, the Z900 detuned for 1976 before the Z1000 replaced it for 1977.

As with most collectable motorcycles the first model is generally the most desirable, and it is the same with the Z1. The 1973 series command the highest prices but if the kudos of owning the first model isn’t important the Z1A and Z1B are almost identical for a lot less investment. The Z1 may not be rare, but it is one of the most significant motorcycles ever, and an all-time classic. It is easy to live with, reliable, and offers performance that isn’t too shabby even by modern standards. It’s not surprising the Z1 has become the classic motorcycle of choice for the cashed-up Baby Boomer.

FIVE THINGS YOU DIDN’T KNOW ABOUT THE Z1

1. As far back as 1967 Kawasaki engineers had plans for a four-stroke super cruiser in the mould of the 1000cc Vincent. Their plan was for a bike that would be easy to ride in any situation, offering unparalleled top gear performance.

2. Code-named the T-103 and “New York Steak” throughout its development period, Kawasaki executive Yoji Hamawaki believed in America the best meal on the menu was a New York Steak and the Z1 represented the same in Kawasaki’s line-up.

3. The Z1 immediately earned a reputation for speed and reliability at Daytona in March 1973. Three motorcycles and a number of riders set forty-five speed and endurance records.

4. Kenny Blake rode a Z1 single-handedly to win the 1973 Castrol Six-Hour production race, defeating the thirstier 750 H2 of Warren Willing and John Boote by 30 seconds.

5. In the US, Dave Aldana won the first Heavyweight Production race at Daytona, Z1s taking the first three places in the 1973 event.