Kawasaki Z900: Do You Remember The First Time?

The following is a re-edit of a piece posted by MotorMartin on DriveTribe under The Junk Yard banner run by Tony Yates, perhaps better known as @Xinterceptor.

Kawasaki are riding the crest of a wave at the moment with an ever expanding range of thoroughly modern motorcycles mixing their traditional values of innovation and power with a subtle helping of Kawasaki Green to help with the styling choices. 

Success on the track has followed many of Kawasaki’s recent technological and engineering choices with a number of British and World Superbike titles following under the stewardship of riders such as Shane ‘Shakey’ Byrne and Jonathan Rea respectively. Indeed, these values have been ever present in all Kawasakis released here in the UK for a number of generations now, with my own 1999 ZX6R G2 living proof that although eighteen years old, there’s just something about Kawasaki sports bikes that captures the imagination and soul once the revs rise quickly and the air box and exhaust start to sing.

Moving on, there was much excitement recently when Kawasaki announced a number of new and revamped machines for 2017 involving the revival of much loved, classic names from their illustrious past. The popular ER-6N and fully faired ER-6F have been extensively reworked and morphed into the classic sounding Z650 and Ninja 650, no longer the across the frame four cylinder of the late seventies and early eighties but thoroughly modern 650 twins. Sportsbike riders, especially SuperSport riders, have been increasingly moving on from ever more frantic and powerful race track refugees and graduating towards the new Adventure styled bikes and Supernaked Street bikes available now. 

And Kawasaki have not been slow in responding to these changing motorcycle trends and have reacted accordingly by creating a family of Supernaked Roadsters with capacity ranging from 250cc up to 1000cc. Amongst all of this activity from Kawasaki’s designers and engineers has been the welcome rebirth of another particularly iconic name to run alongside the previously mentioned Z650. 

Ask anyone of a certain age what was the first Japanese Superbike and the answer will inevitably be the Kawasaki Z1 of 1972, an across the frame four cylinder machine which debuted Kawasaki’s timeless styling, styling that was repeated on a whole range of bikes culminating in the beginning of arguably the first modern retro motorcycles in the guise of the Zephyr 550, 750 and eventually the pinnacle of the Zephyr range, the mighty 1100. The Z1 was released to an unsuspecting public on the coat tails of the Honda CB750 of 1969 and took the fight straight to Honda themselves. 

A history lesson I think. The Kawasaki Z1 went on sale in America in 1972 and The UK in ’73, causing quite a stir due to the increase in capacity over Honda’s 750. Things were happening quickly during the design process as prototypes disguised as Honda CB750s were out and about on the roads of America by 1971, clocking up big mileages to make sure that everything was right first time. 

Respected motorcycle journalist Rod Ker gives us some background technical information regarding the engine as he states: Kawasaki’s four stored its oil in the sump, and used a built-up roller bearing crankshaft, with gear primary drive. In some respects the bottom end therefore had a few things in common with the company’s two-strokes. A central roller chain drove a pair of camshafts, effectively running in the cylinder head (in replaceable split shell bearings), opening the valves directly through bucket tappets, with clearances adjustable by shims. Breathing through a quartet of 28mm carburettors, Kawasaki claimed 82PS at 8500rpm. The crucial bit was that this was about 15bhp more than the CB750! In terms of specific output, the two were therefore very close.

All of which engineering was essential as Kawasaki were adamant that their inaugural SuperBike would not be perceived as under engineered. So right was their original engine architecture that it lasted until around 2000 with the aforementioned Zephyr 1100, a development of the GPz1100 which was itself a development of the original Z1. Now that is certainly a strong and impressive family tree. The 903cc engine became 1015cc for the Z1000 in 1977 with the bore taken out from 66 to 70mm.

In fact, over time, the original Z1 changed very little, so correct was the original design at launch that there really was no need for the type of rapid development and wholesale changes that we have got used to these days within a two year cycle for any particular model. In 1971 the Z1 changed into the Z1-A with the cylinder block changing from black to a bare alloy finish, new paint designs and the addition of a brake light warning bulb in the tachometer. Busy times for those Kawasaki engineers perhaps. 1975 saw the Z1-B gain new sidecover badges and an O-ring chain whilst it’s chain oiling system was quietly dropped and then in 1976 came the introduction of the now legendary 900 moniker with the Z900-A. In a fit of uncharacteristic work at Kawasaki’s design, engineering and manufacturing department, the Z900 now boasted of a braced frame, 26mm carburettors, a new air cleaner, smaller battery/mount, twin discs, a fuel cap lock, new 4 into 4 exhaust, rear mudguard, seat, fork sliders and internals.

The Z900’s popularity has been undiminished over the last 43 years or so since its original unveiling with the models quirks and weak points discussed at length by restorers and historians yet the Kawasaki’s reputation is continuing to rise with prices for the very best machines beginning to nudge the £20,000 barrier and even slightly down at heel originals reaching nearly £10,000 or more. After all, this is still a stunningly beautiful machine complimented superbly by it’s 4 into 4 chrome exhaust system. 

Fans can now rejoice though as the legendary Z900 name has been revitalised with its appropriation by the very latest Supernaked with Kawasaki themselves stating: Iconic Z900 name re-born. A cutting edge rider-focused Supernaked with the sublime balance of power and handling. The tubular trellis frame houses a willing and responsive 4-Cylinder engine while the styling and rider experience reflect a refined and raw feeling that only Z riders can experience. Kawasaki Z900, Refined Raw.

With styling that offers a nod towards that original Z1 of 1973 yet still providing the rider with a thoroughly modern and up to date motorbike, Kawasaki have another winner on their hands, if early reviews in the U.K. Motorcycle press are anything to go by and I’ve no doubt that we’ll soon be seeing a whole new generation of Kawasaki fans riding their Z900 across the highways and byways of this green and pleasant land of ours and you know what? I can’t wait.

Where will you go?

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