Kawasaki found a major recipe for success when it released its H1 at the tail-end of the ’60s. Though the bar had been set pretty high with the 500, Team Green managed to outdo themselves and deliver an even more iconic, game-changing machine with the H2 in the early ‘70s. So when a few years passed, the Z1 came and went, and it came time for the Japanese marque to introduce yet another, new flagship model, the company knew it had its work cut out for it.
Originally Kawasaki had green lit the development of a liquid-cooled, two-stroke, three-quarter-liter four, and a rotary mill, but both projects were scrapped on account of the ongoing world-wide oil shortage/crisis. Despite the bump in fuel prices, the Z1 was still generating positive sales numbers, so the year before the 900cc inline-four was pulled from production, Kawa secretly got the ball rolling on developing what would be its next beast of a flagship model.
Kawasaki’s R&D team was tasked with three primary objectives: create a new motorcycle utilizing the latest available technology, build a machine that was more powerful than its predecessors, and deliver said machine in a large enough displacement to denote the model’s flagship status. So after running the numbers, the lab coats landed on a 1.2 liter displacement. But instead of simply boring out the Z1, Kawasaki opted to experiment with less-conventional engine configurations, including a square-four and a V-4.
Supposedly Kawasaki’s American division was the first to suggest an inline-six — a type of engine Kawa had never produced before. The new six-barrel would utilize a single-piece plain-bearing crank (unlike the built up unit found in the Z1) which was strengthened to prevent twisting. With Kawasaki’s engineers anticipating a 120 hp output from the 1,200 cc six, a lot of focus was placed on reinforcing highly stressed components. The frame also received a reinforced steering head to deal with said power.
Around this same time, Kawasaki was one of Japan’s leading transmission manufacturers, and Team Green routinely produced trannies for auto companies like Isuzu. So Kawasaki got resourceful and assigned its transmissions team to develop a shaft drive system for the new 120 hp flagship model. Because the bike was classified as a sport tourer, the shaft final drive was fairly practical.
By 1976 Kawasaki had completed its first prototype of the six-cylinder beast, dressing the heavyweight up in 1970’s super-sport style. Unfortunately, in the time that had passed since the six’s development began, sport aesthetics were on the decline, and big-body tourers were all the rage. In response, Kawa stripped off the sport plastics and tacked on more touring-oriented fairings and a larger tank.
The next year, news broke that Harley-Davidson was set to release a new 1,340 cc engine. Not wanting to be outdone, Kawasaki decided to bump the KZ proto’s displacement up to 1,286cc. By March of ’78, Kawasaki finished its final engine prototype and began tweaking the chassis. The ultimate goal was to ensure the KZ1300’s performance was on par with the smaller Z1. After months of tuning the frame geometry and suspension, Kawasaki felt its new flagship was ready to be unleashed onto the motorcycling world.
In September of ’78 the cover was pulled off the KZ1300 for the first time at the Koln Motor Show. The general public reacted well to the new model, however the real test would come the following month when motorcycle journalists would swing a leg over the 1300 for the first time. Despite weighing in at around 700 lbs (wet), the liquid-cooled, 1,286 cc, DOHC, two-valve, six-cylinder block was supposedly capable of getting the KZ up to around 140 mph thanks to its claimed 120 hp at 6,000 rpm and 85 ft-lbs of torque at 6,000 rpm. The media was generally impressed with the behemoth bike’s performance, even with its less-than-stellar ground clearance.
Upon the release of the KZ1300 (or the Z1300 as it was known in some regions), sales were decent, though there was still a lot of room for improvement on Kawa’s new flagship. Half-a-decade after going into production, Kawasaki opted to revise the machine, giving it digital fuel injection which earned it the new moniker of the “ZG1300” (depending on region). While the addition of fuel injection was done to improve fuel economy, it had the added benefit of also boosting power.
1983 was also the year that Kawasaki released the bonafide touring variant of the 1300 which would be known as the (ZN1300A) “Voyager”. The Voyager was a full dresser, completed with large stepped seating, AM/FM radio, stopwatch and calculator for fuel calculations, cassette deck, trip computer, fuel-gauge, trunk and luggage, digital instrumentation, etc. While the Voyager ultimately proved to be a success in the US market, only approximately one-fifth of KZ1300’s ever produced Voyager-specs (4,500 Voyagers and 20,000 KZ1300s). The last 500 units produced were reportedly called “Legendary Six”s — a distinction that could be seen on the tank.
The KZ1300 would remain in production for more than a decade before Kawasaki finally retired the big six. Since then, multiple outfits have turned to the six-cylinder Kawa mill when looking to cook up some beastly vehicle, including in 1982 when Swiss car company Franco Sbarro built a 12-cylinder car by combining two KZ1300 engines, and in 2008 when Allen Millyard created a custom 2,300cc version of the KZ, again using two engines. The history of the production six-cylinder motorcycle is an interesting one, and it’s hard to find a better writeup on the subject than this Cycle World piece that compares the Benelli 900 Sei, Honda CBX1000, and KZ1300.
This particular KZ example – which has 17,000 miles on the odo – has been fully restored and is said to be in “perfect running condition”. On top of its mechanical state, this example also boasts a few upgrades such as ZRX suspenders in back, ZRX rearsets, and the “popular CB1100 coils upgrade”. The brakes and fork seals were also recently replaced, and as the icing on the cake, this example has just been hit with a fresh coat of paint in the form of an ELR (Eddie Lawson Replica) livery.
You can find this restored 1979 Kawasaki KZ1300 for sale here on Craigslist on Long Island, New York with a price of $6,500.