Sold until 1982, with its 2-stroke 3-cylinder sound and unique character!
In 1969, Kawasaki released a three-cylinder, 500cc two-stroke machine that was an evolution of the 250cc A1 and 350cc A7, as a pioneer in its move into the global market.
Named the Mach III, it was a monster of a machine with a top speed of 200km/h, could sprint from 0 to 400m in 12 seconds, and could do a wheelie in the blink of an eye if the throttle was opened wide.
Next, in 1971, the 350SS was released, scaled down to 350cc, and as the only three-cylinder in the medium-sized class with many users, it made an offensive into Japan.
The three-cylinder, 346cc engine with a bore and stroke of 53 x 52.3mm produced an ultra-powerful 45PS/8,000rpm and 4.25kgm/7,000rpm.
When revved up to its peak speed, it showed an intense dash reminiscent of the 500cc Mach III.
With this momentum, Kawasaki wanted to make its name known to the world in one fell swoop, so they released the Z1, the first four-stroke, 900cc, four-cylinder big bike, and then added the 750cc Mach IV and 350cc Mach II to the Mach series, which had been their flagship model until then, as two-stroke, three-cylinder series, and in 1972 they introduced the last of the three, the 250cc Mach I.
However, in the 350cc mid-size class, there were already 4-stroke sports models, and compared to their easy-to-handle torque at low and mid-range, the peaky 2-strokes were hard to beat.
But the 2-stroke, 3-cylinder engines, which explode evenly at a 120° crank, have a unique exhaust note. The 3-cylinder exhaust sound resonates, producing a 'voo' sound with a glottal stop on the 'u' in the mid-range, and a 'gyoon!' sound at the peak of the high-rpm range, and an increasing number of potential riders were attracted to this strong individuality.
So in 1974, the 400SS, a 400cc version with the 350's bore enlarged to 57mm, was released.
In exchange for reducing peak power to 41PS, the engine was transformed into one that emphasized ease of riding with good response from the mid-range onwards.
The almost vibration-free smoothness of the 120° crank was also well received, and its rider-friendly impression made it popular with beginners as well.
The lubricating oil unique to 2-strokes burned and produced a lot of white smoke, which, along with the sound, began to be talked about as one of its unique features.
The 400SS was later redesigned into the KH400, with peak power further reduced to make it easier to ride, and the movement to make the unique character of a 2-stroke 3-cylinder engine accessible even to beginners was established. The KH model name was changed to "Ketch" and it was classified as something different from the peaky 3-cylinder engines that had been available up until then.
However, four-strokes took over the market not only in Japan but also around the world, and Mach's KH series became a minor presence.
Nevertheless, the demand for the KH400 and KH250 did not suddenly drop due to their rarity as unique two-stroke, three-cylinder engines, and they remained in the catalogue until 1982, and their popularity on the used car market has continued unabated ever since.
→Read the full story (JP Website)
See KAWASAKI KH400 Moto Index Page
Information Source. [ RIDE HI ]
