Moto Guzzi 254 and Kawasaki S1 | Motorcycle History
by Gary IlminenWhen you bring up dazzling, technically sophisticated motorcycles with engine designs that made a mark on the sport, many enthusiasts tend to think of Honda’s CB 750 four of the late sixties or the six-cylinder 1047cc CBX of the late seventies or the Benelli Sei.
Classic-minded riders may recall the 441 Indian, Henderson, or Cleveland in-line fours. Road racing fans may include the five-cylinder Honda 125 cc RC 149 or the Honda RC 165 six-cylinder 250 cc GP bikes of the sixties. They may think of the 1000 cc V-6 Laverda endurance racer of 1978. Or, they may recall the incredible 500 cc Moto-Guzzi V-8 GP racer of 1955-7.
But, there are some superbikes—well, somewhat super—that have been overlooked. Let’s call them the mighty mini-multis.
For example, about 20 years after Moto-Guzzi dazzled the GP racing circuit with its V-8, and after its merger with the De Tomaso Group, it produced one of the most interesting mighty mini-multis ever built for the consumer market. It was known simply as the 254.
Introduced in early 1978, the 254 (also marketed as the Benelli 250 Quattro and in 1979 offered as a 350 four, as well) featured ultra-sleek Euro styling and a nifty air-cooled engine that weighed only 78 pounds without its four 18 mm Dell ‘Orto carbs and 4-into-2 exhaust system. It produced a claimed 28 BHP at 10,500 RPM, fed to the rear wheel through a five speed transmission with chain final drive. The short-stroke (B/S: 44 mm x 38 mm) engine could easily whirl to its 11,800 RPM redline. Claimed top speed was 93 MPH.
Brian Tarbox, noted UK motorcycle journalist, tested the 254 in Italy prior to its market release in 1977, when he was working for Motorcycle News.
“I was a guest of the Moto Guzzi factory in Italy for an exclusive test in about 1977. At that time Moto Guzzi and Benelli were part of the same industrial group and this four-cylinder machine was produced under both brand names. The Moto Guzzi had far more radical styling,” Tarbox recalled.
“However, a drawback to that styling was a minute petrol tank. When revved hard, fuel consumption could fall to about 35mpg. This meant there were areas of Britain, particularly Scotland, where the size of the tank was insufficient to get you from one petrol station to the next.
“As a result, the UK importers decided against bringing it to this country. However, it was a great little bike and I have great memories of riding it through the countryside of Northern Italy.”
Indeed, the plastic gas tank fitted to the Moto Guzzi 254 held only 2.2 US gallons of fuel (8.5 L). Assuming the bike could achieve its stated average fuel economy of 39 MPG that would leave the rider running on vapors after only 85 miles; only 77 miles when pushed as Tarbox describes.
Despite its range limitations, the 254 was an innovative design with a number of features ahead of its time.
It made extensive use of plastic and aluminum to hold its weight down to 278 lbs. To keep the bars lean and clean, the reservoir for the front hydraulic single disc brake was concealed down on the frame, nestled in with the fuel tank under the plastic shroud that covered the tank itself. Even the instruments were located in the top of the tank area, which kept the view over the bars very clean, but further reduced the volume of the fuel tank.
The mighty mini-multi class wasn’t limited to this diminutive four-stroke, though. A few years earlier, a two-stroke quarter-liter triple was built in Japan by Kawasaki from 1972 to 1980.
Following on the fearsome 500 cc two-stroke triple called the H1 Mach III unleashed in 1969, Kawasaki broadened the line of two-stroke triples to include the ferocious H2 Mach IV 750 cc, the S2 Mach II 350 cc—later as a 400—and the S1 Mach I 250 cc.
The Kawasaki S1’s air-cooled, oil injected engine developed a claimed 32 horsepower at 8,500 RPM. The comparatively long stroke (B/S 45 mm x 52.3 mm) piston-port engine revved with amazing rapidity—and it had to in order to make its power, which was sent to the pavement through a five speed gearbox and chain final drive.
Weighing in at about 326 lbs., and using rather more conventional design elements in the fuel tank, instruments and materials in most areas of construction, the S1 could muster a claimed maximum speed of about 105 MPH, though that may have been a bit of a stretch.
The engine was fueled through three VM22SC carburetors, which even when ridden with some degree of restraint could make the S1 a little thirsty. The long, sleek S1 fuel tank carried 3.7 gallons. Stopping power for the S1 was provided by drum brakes front and rear until the 1976 model year when a single piston caliper disc brake became standard up front.
The S1 is one of the few 70s vintage road bikes Brian Tarbox has not road tested and written about, but he does have some interesting things to say about it, especially from the viewpoint of the vintage bike enthusiast.
“The S1 250 is highly regarded and is said by some enthusiasts to be capable of nearly 100mph. I never rode one of these but in Britain they are rare and highly desirable and their price reflects that. To the layman, the later KH 250 version of the same bike is more or less the same thing. But not so to the enthusiast. People who would sell their granny for an S1 250 would not take a KH 250 as a present. The KH was much slower and, I believe, heavier,” he says.
“The problem with both the three-cylinder 250 Kawasaki and the Benelli/Moto Guzzi 250-4 is summed up in one word – Yamaha. The RD 250 Yamaha and the 400 that followed were cheap, simple, fantastic value for money and were fast and handled well. The Italian fours were not in the same performance class and a good S1 Kawasaki would in Britain today fetch three times the price of an RD 250 or 400.”
While many motorcycle buyers in the 1970s were being wooed and wowed by the ever larger, ever faster assortment of multi-cylinder bikes, there was a small but highly discriminating group of buyers who wanted such technical refinement on a smaller, less brutish scale.
For those buyers, at least two manufacturers stepped up with mighty mini-multis that filled the bill whether it was two or four stroke power they preferred. In the end, each of these bikes has to be considered a quarter-liter classic.