The S3 Mach II 400 was a smaller, more tamable version of Kawasaki’s legendary 1970’s triples, though the 400 two-stroke inline-triple still packed enough punch to allow for some legally-questionable riding. After Kawasaki’s enormous success with the release of its H1 Mach III, Mean Green seized on the momentum of its iconic three-cylinder by offering several other bikes powered by the two-stroke triple that had put Kawasaki back on the map at the start of the ’70’s. Within three years of the H1’s release, Kawa had debuted three more three-cylinder oil-burners in the form of the 250cc S1 Mach I, 350cc S2 Mach II, and the wildly popular 750cc H2 Mach IV.
Unlike what they did with the 250, Kawasaki opted to pour a substantial amount of resources into further developing the 350 S2 Mach II. Two years after its debut, Kawasaki justified a name change after giving the 350 an updated chassis that housed an engine with an extra 50cc’s, resulting in the S3 Mach II. The new power plant – while lethargic at low rpm – sprang to life somewhere around 5,500rpm. The S3’s 400cc air-cooled, two-stroke, three-pot engine made a respectable 42hp at 7,000rpm. Weighing in at 339lbs (dry), the S3 – which was produced in ’74 and ’75 – boasted a top speed in the 100 mph ballpark.
A big part of what made the S3 so noteworthy was its agile handling. In the January issue of Cycle World in ’74 the publication described the 400 cc Mach II saying: “It can be flicked from side to side, power on, except in the first two gears. In that situation you have to ease the power on to keep the front wheel down. If it had a little more power, production racing the 400 could be lucrative.” The bike’s sub-350 lb weight didn’t hurt its handling either. Furthering the S3’s popularity was the fact that in 1975 the Mach II 400 reportedly sold new for $935, while Honda’s CB400F went for $1,470.
This unrestored 1974 S3 400 example is by no means a show-bike, but it is pretty clean, still wearing its original factory coat of metallic turquoise paint. The tank’s appearance is a crucial part of what gives this bike its old-school charm. The Kawasaki type is knocked out of the light blue highlight with the tank’s primary color coming though (in negative space) as the color of the Kawasaki-lettering. A single white-stripe encircling the manufacturer’s name, as well as the distinctly vintage typography/font give the S3 a lot of its character, along with the asymmetrical three-pipe exhaust and sporty rear cowl.
The example has a clean title and was recently given new tires, battery, chain, sprockets, and clutch. According to the owner, the bike has a few imperfections in the form of scratches, chips and some rust, but the seat is immaculate and it’s said to be very mechanically sound. It also appears that the current seller owns or works for TripleStuff.net, with the ad saying: “I have just about any Kawasaki triple part for sale,” and then listing the aforementioned URL. The ad also includes a link to a YouTube video that shows a thorough walk-around and the bike being fired up:
You can find this 1974 Kawasaki S3 Mach II 400 triple example for sale here on Craigslist in Los Angeles, California with a price of $4,800.