Super Four: 1973 Kawasaki Z-1

Americans would’ve settled for a burger; Kawasaki gave them steak. The Z-1 roared off the block in 1973 breaking records, “Terribly fast. Two words every motorcyclist loves to hear.”

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by Dain Gingerelli

Engine: 903cc air-cooled DOHC inline 4-cylinder, 66mm x 66mm bore and stroke, 8.5:1 compression ratio, 82hp @ 8,500rpm
Top speed: 120mph-plus (period tests)
Carburetion: Four 28mm Mikuni VM
Transmission: 5-speed, chain final drive
Electrics: 12v, coil and breaker points ignition
Frame/wheelbase: Dual downtube steel cradle frame/58.7in (1,491mm)
Suspension: Telescopic forks front, twin shock absorbers w/ adjustable preload rear
Brakes: 11.5in (292mm) disc brake front, 7.9in (200mm) drum rear
Tires: 3.25 x 19in front, 4 x 18in rear
Weight: 542lb (246kg)
Seat height: 31.5in (800mm)
Fuel capacity/MPG: 4.76gal (18ltr)
Price then/now: $1,895/$5,000-$24,000

Author’s note: The following story has all the drama of a Shakespeare play, highlighting the near-fall, yet ultimate success of a landmark motorcycle, the push and pull struggle between two of the motorcycle industry’s titans, the tragic death of a young man, and finally the recovery of an original 1973 Kawasaki Z-1 that registers only 9.8 miles on its odometer. This is the story of Z1E 00004. — DG

No doubt, 1969 was a transitional, even pivotal, year for motorcycling. Foremost, two landmark models made their mark during that year when Honda crammed as many of its new CB750 Fours as its factory could produce into dealer showrooms, while Kawasaki crowded the drag strips of America with countless, and extremely potent, Mach III triples, aka The Rocket with a Sprocket.

Kawasaki also used 1969 as a time to reconsider its intentions of a future model under development. That project, known within Kawasaki confines in late 1968 as N600, had come to an unexpected halt in October 1968 when Honda unveiled its CB750 Four at the Tokyo Motor Show. By chance Kawasaki had been developing a similar product — the N600 — that also happened to be powered by an inline 4-cylinder 750cc engine. News of Honda’s groundbreaking 750 prompted Kawasaki to suspend the N600, using the timeout for a rethink; in the time-honored way of the samurai, it would be shameful to follow through with the N600 now. So after careful consideration Kawasaki majordomos did what any smart samurai warrior would do — they reached for a bigger sword.

Beginnings of the Z-1

The new sword — the engine, if you will — displaced 903 cubic centimeters. The outcome of the realigned project, eventually completed in mid-1972, was the Z-1. And, as history has told us, the Z-1 proved to be another milestone motorcycle, this one in model-year 1973, and so the motorcycle community in 1969 would have to wait a few years for the Z-1. Even so, Kawasaki’s future held promise when the 1960s, a swash-buckling decade if there ever was one, reached its just conclusion.

We’ll return to the future in a minute, but first let’s time travel back to 1969 for a peek-see at what course of action Kawasaki planners took to achieve their new 903cc engine. Rather than completely scrap the N600 project, Kawasaki elected to see just how far they could stretch the prototype engine’s displacement that would, in the process, upstage Honda’s paltry three-quarter-liter engine. The tolerable limit turned out to be 903 cubic centimeters, so that’s what they ran with, and N600 suddenly became T103. For the time being, anyway, because as development progressed, in-house memos eventually would identify the gestating product as 0030 and eventually 9057 when it reached pre-production prototype stage in early 1972. The project also earned another unofficial moniker — New York Steak — but that’s a story in itself (see sidebar).

Essentially, though, N600-cum-T103 had its origins when, in 1967, Kawasaki executives in Japan created what they termed their “market-in” strategy for American customers. Rather than follow the Japanese time-honored method of building products that suited their domestic market and simply pass along those same models to American consumers, Kawasaki elected to talk directly with U.S. dealers to ask their opinions about customer preferences, and then plan their U.S. product line accordingly.

Kawasaki management rightfully concluded that U.S. dealers knew their clientele best. Product planners also turned to members of Kawasaki Heavy Industries’ (KHI) newly formed U.S. distributor, Kawasaki Motor Corp. (KMC) that eventually settled in Santa Ana, California, for further input. (Currently headquarters are in Foothill Ranch, California.)

The combined research in 1968 revealed that Americans wanted a bike with a large-displacement 4-stroke engine. Mutterings of an engine using four inline cylinders were part of that final feedback, too. And so, sometime in 1968 a folder labeled “N600” found its way into the KHI product planner’s file cabinet, and work began. Then came Black October 1968 (the debut of the CB750).

Shortly after the initial October shock, work continued as N600 begat T103. No target date was set, but KHI players agreed that the reconfigured bike should be on the market sooner, rather than later.

KHI’s market-in strategy also led to KMC hiring Bryon Farnsworth — at the time Cycle magazine’s West Coast Editor — in 1971 to serve as an in-house liaison between Japan and the U.S. for T103. By October of that year two other members from KMC, Randy Hall serving as manager for the U.S. road race team and Jim Corpe from Technical Services Department, were sent to Japan to ride and give their impressions of the project’s running prototypes.

As Hall wrote in his new book Lean, Mean and Lime Green! Volume 1, he and Corpe were requested by Sadaichi “Sid” Saito, engineering coordinator between KHI and KMC, to ride the bikes and then report their findings directly to Misoa “Lyndon” Yurikusa, who oversaw testing and racing development at KHI. As Hall stated in his book, “Jim and I rode the pre-production Z-1 motorcycles on city streets, over mountain roads on Mount Morioka and at Yatabe (Japanese motor industry test track). Yatabe is a 3.6-mile-long four-lane-wide oval layout test track with long straights, and bowl-shaped banked corners reminiscent of the old Monza racetrack in Italy.”

According to Hall, during one lap his test bike’s speedometer registered 139mph. “And even with an optimistic speedometer,” Hall concluded, “this was unbelievably fast for a production road-going motorcycle at that time.”

In the metal

By late spring 1972 the project was near completion, and the Akashi plant was set to build a handful of bikes, now officially designated the Z-1. (According to sources, the Z designation was in honor of the original Meguro Z97, a bike produced in the late 1930s by the company that eventually became Kawasaki Motors). These were among a batch to be reserved for a very special press preview limited to four American motorcycle magazine editors, Ivan Wagar, Cook Neilson, Bob Braverman and Bob Greene, from the leading motorcycle publications at the time — Cycle World, Cycle, Cycle Guide and Motorcyclist respectively. The Z-1 reveal took place in Japan, and by the end of their five-day press junket the editors returned home rather impressed with what they saw.

Wagar extolled the new engine’s virtues at various points in his October 1972 report for Cycle World, citing very mild cam timing. “So modest are the timing figures,” Wagar wrote, “I predict very shortly there will be a horde of aftermarket hop-up cams available for this machine.” His words were an understatement about the future tsunami of aftermarket cam suppliers. He also acknowledged the Z-1’s low 8.5:1 compression ratio such that KHI testers “found that the very worst grade of gasoline available would not produce pinging.” His observations reveal just how much Kawasaki under-engineered the engine, yet it was capable of powering the bike to speeds in excess of 130mph.

Perhaps Cycle magazine summed it up best in its Superbike Shootout for the December 1972 issue. Summarizing the Z-1 (which finished a close second to Kawasaki’s other super legend, the 2-stroke triple 750cc Mach IV), Cycle stated: “The rangy Z1, the same motorcycle we tested in the November issue, offers performance a whisker away from that of the Mach IV with none of its sibling’s drawbacks. It’s quiet, pleasant, easy to deal with, consistent, and terribly fast.” [Note: Cycle wrote “Z1” without the hyphen in the middle. The “Z1” designation is used in another magazine quote later in this article. 1973 Kawasaki literature and ads show “Z-1,” not “Z1,” but subsequent documents sometimes show Z1. Magazine reports/road tests from the era show differing styles, too. — DG]

On track

Terribly fast. Two words that practically every motorcyclist loves to hear. And the “terribly fast” Z-1 was on its way to the shores of America. By the end of 1973 several thousand examples of the “terribly fast” Superbike could be found on the streets, highways and byways of America. Like 1969, 1973 proved to be a pivotal year for motorcycling. The year even included a race win by Canadian ace road racer Yvon Duhamel aboard a Yoshimura-prepped Z-1 in what amounts to the first-ever Superbike race. Duhamel’s win was part of a support feature event for the 1973 AMA National Road Race at Laguna Seca, officially designated the Kawasaki Superbike International. The race that Duhamel won, with teammate Steve McLaughlin finishing second, was termed the Open Production Race, but promoters Trippe-Cox and Associates changed the name to the Superbike Race the following year, and by 1976 the AMA officially adopted the name Superbike for its national series. Today the name Superbike is as generic among the motorcycle community as the words “horsepower” or “speed.”

Clearly, and even in its stock configuration, Kawasaki’s Z-1 was a Superbike for the times. Period magazine tests posted quarter-mile figures of low 12-second ETs, with terminal speeds at or above 110mph. To further make a point, Cycle World featured a Yoshimura-modified street-going Z-1 that zipped through the quarter-mile Armco gauntlet with a staggering 11.40-second ET at 116.88mph. KMC even prepped two standard-issue Z-1s for an assault on the 24-hour world speed/endurance record at Daytona International Speedway in March 1973. When the timers stopped the clock 24 hours later one bike had covered 2,631.402 miles, averaging 109.641mph — a new world record. Another Yoshimura-modified bike ridden by Duhamel set a closed-course speed of 160.214mph, along with several other speed records. In all, the new Z-1 accounted for 46 world and national records that week.

On the street

But for the most part, the thousands of Z-1s sold in 1973 were ridden on the street by ordinary people who just happened to like terribly fast motorcycles. Precisely how many Z-1s were built that year remains a matter of what numbers you want to believe, but one thing is for certain: The bike featured here, Z1E 00004, is one of a very small and elite number that have never been licensed for the street. According to various sources, 00004 was initially presented to KMC Midwest distributor executive Dave Meheney for use as a promotional tool for his sales region. One way or another, the bike, still resting quietly and safely in its crate, wound up at World of Cycles’ Vista Kawasaki (owned by Jack Brooks and Terry Bolling) in Louisville, Kentucky. The bike’s status remained undisturbed until 1979 when one of the shop’s employees, a young man named Robert Bone, realized the significance of the landmark model and begged to buy it, still in its crate. With the help of his mother co-signing for the loan, young Bone promptly stored the crated bike in his family’s garage. Tragically, a couple of years later he lost his life in a truck accident, but in memory of their son the Bone family kept the bike for several more years until Bone’s mother contacted KMC executive Bob Moffit to see if the California-based company would be interested in acquiring Z1E 00004 for the company’s archival use. Moffit realized the importance of this early model and made arrangements to purchase the bike, and with the blessing of KMC’s president, Misao “Lyndon” Yurikusa (who also was one of the key players in the Z-1’s genesis), 00004 found its way back to the distributorship’s headquarters where it’s now enshrined at KMC’s Heritage Hall Museum in Foothill Ranch, California.

Norm Bigelow, a retired KMC employee who currently serves as the museum’s curator, recalls spotting 00004 tucked away in a storage room at KMC’s Irvine building prior to Kawasaki’s 40th anniversary dealer show. The bike still had much of its original dust on it, so rather than spend time cleaning the bike, Norm borrowed a friend’s immaculate Z-1 to display at the show. A short time later Mitch Boehm, editor for MotorcyclistRetro, asked to borrow 00004 for a feature in the magazine. Out popped Norm’s cleaning utensils and off came the bike’s dust, some of it dating back to 1973. The bike received its just reward, appearing on the cover of the Fall 2008 issue.

As Norm recalls, “It [00004] had what amounted to inspection mileage on it from the factory, but most of the miles showing on the odometer are simply ‘push miles’ from rolling the bike at shows and such.”

At the time of our photo session, the odometer displayed less than 10 miles. The length of the KMC parking lot that we rolled the bike across to get to our desired location prompted the odometer numbers to flip some more, but not beyond 10 miles. As of our photo session in December 2018 the odometer read precisely 9.8 miles.

Regardless of what mileage shows on the odometer, the fact remains, Norm and I never fired the engine up during our photo session, thus helping preserve that part of motorcycling history for generations to come. 00004’s integrity remains intact. As does the Z-1’s legacy itself. Truly a terribly fast and remarkable motorcycle for its time, and for all time. MC

Let them eat Steak!

Corporate spying has always played a mischievous role in the industrialized world. Companies do whatever they can to maintain a sales edge over competitors, prompting the use of code names to help conceal various prototypes and secret future products from outsiders.

Beyond the Z-1’s early N600 and subsequent code names, the Z-1 project also carried the unofficial in-house moniker “New York Steak.” There are several explanations about how that came to be, but two related stories seem to share the most credence. One interpretation by Yoji Hamawaki, former president of KMC, credits Americans’ appetite (literally) for a good New York steak. Mr. Hamawaki told Marc Cook, editor of Motorcyclist magazine at the time, that the New York Steak name reflected the Z-1’s placement in Kawasaki’s model lineup. As Marc Cook quoted Mr. Hamawaki in the publication’s December 2012 issue, “We knew that in America the best meal on the menu was the New York steak. In our minds, the Z1 was going to be the best motorcycle we could make, the top of the menu.” So soon enough many of N600’s key players referred to their project as New York Steak. The name stuck.

Sam Tanegashima, project leader for the Z-1, offered additional insight: In 1968 he conducted an extensive and rather exhaustive trip to about 30 Kawasaki dealers in America to learn what kind of big-bore engine U.S. riders preferred. He also asked the leading motorcycle magazine editors the same relative question, and the majority agreed that Yanks wanted a 500cc 4-stroke single for off-road purposes, a conclusion likely enhanced by the growing popularity of dual-sport motorcycles at the time.

When Mr. Tanegashima reported his findings to Mr. Hamawaki and two American KMC employees, Alan Masek (KMC’s general manager) and Dave Graves (vice president of sales), the three were slightly taken aback. All had figured that Mr. Tanegashima’s findings would cite a desire for an inline 4-cylinder, 4-stroke engine. But as Tanegashima related years later, Hamawaki replied that a 500 single was “lobster” compared to that of a 750cc inline four — New York steak. “Lobster is good, but steak is better,” Hamawaki had replied, and from that point on when project personnel referenced the new multi-cylinder engine, they often used the words New York Steak to do so. — Dain Gingerelli

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