Kawasaki A1 Samurai
Encyclopedia
The A1 Samurai was a 250 cc production motorcycle
made by Kawasaki. It was a standard or Universal Japanese motorcycle sold in the US and abroad from 1967 through 1971.
did not sell as expected, because all rival bikes were still faster, lighter and had better steering. Kawasaki developed the lighter A1 Samurai in 1967. The A1 took center stage as a high-performance machine, with approximately 80ps per liter. It was quickly followed by a larger-bore model, the Kawasaki A7 Avenger
which shared most of the Samurai components except the motor.
. The engine's ignition air supply began in an air filter
canister below the seat and was pulled through a large plenum chamber
just above the transmission
and behind the cylinder head
then downward into the two internal passages leading to the carburetor
housing feeding the carburetors. The A1 had two Mikuni carburetors located on the engine's left and right sides and inline with the crankshaft
. The carburetors were enclosed and protected from the elements by carburetor covers fixed to the crankcase
. Inboard of each carburetor, and supporting each carburetor, was the disc cover. The rotary disc valve was housed inboard of that cover. The A1 Samurai motor was lubricated by the Superlube system, with 2-stroke oil directly injected in the intake tract.
Previously equipped with points, the ignition system
was equipped in 1969 with a Capacitor discharge ignition
including thyristor
-based switching system then increased the voltage to between 25,000 and 30,000 volts reducing the unburned fuel mixture within the cylinders.
This combination of displacement (247cc), CDI system, and rotary discs produced 31 hp (23.1 KW) @ 8000 RPM gave the Samurai a power-to-weight ratio of 1 horsepower per 11 pounds of weight, a 0-60 mph of 6.6 second, making the Samurai as fast or faster than production competitors in its class.
(AHRMA) comoetition.
Kawasaki Mach III's successfully raced with Ginger Molloy aboard his "Green Meanie" finishing 2nd just behind Giacomo Agostini's MV Agusta
in the 1970 500cc World Championship. Kawasaki's
Motorcycle
A motorcycle is a single-track, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.Motorcycles are one of the most...
made by Kawasaki. It was a standard or Universal Japanese motorcycle sold in the US and abroad from 1967 through 1971.
Development
The Kawasaki W1Kawasaki W series
-Antecedents: Meguro K series:In 1960 the Akashi-based Kawasaki Aircraft Company acquired an interest in the Meguro motorcycle company, which had obtained a license to produce a copy of the 500 cc BSA A7. Meguro had been Japan's largest motorcycle manufacturer but in the late 1950s its models had...
did not sell as expected, because all rival bikes were still faster, lighter and had better steering. Kawasaki developed the lighter A1 Samurai in 1967. The A1 took center stage as a high-performance machine, with approximately 80ps per liter. It was quickly followed by a larger-bore model, the Kawasaki A7 Avenger
Kawasaki A7 Avenger
The A7 Avenger was a Kawasaki motorcycle. It was a standard or Universal Japanese motorcycle sold in the U.S. and abroad from 1967 through 1971.-Development:Kawasaki was the last of the big four Japanese manufacturers to start making motorcycles...
which shared most of the Samurai components except the motor.
A1SS
The A1SS Samurai has a crossover dual exhaust mounted on the left side and just below the seat. Other than exhaust system, there were no other changes between the standard A1 and A1SS.A unique engine
The engine was a unique 2-cylinder, two-stroke, air-cooled, oil-injected, dual rotary disc valveRotary valve
A rotary valve is a type of valve in which the rotation of a passage or passages in a transverse plug regulates the flow of liquid or gas through the attached pipes. The common stopcock is the simplest form of rotary valve...
. The engine's ignition air supply began in an air filter
Air filter
A particulate air filter is a device composed of fibrous materials which removes solid particulates such as dust, pollen, mold, and bacteria from the air. A chemical air filter consists of an absorbent or catalyst for the removal of airborne molecular contaminants such as volatile organic compounds...
canister below the seat and was pulled through a large plenum chamber
Plenum chamber
A plenum chamber is a pressurised housing containing a gas or fluid at positive pressure . One function of the plenum can be to equalise pressure for more even distribution, because of irregular supply or demand...
just above the transmission
Transmission (mechanics)
A machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as: an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a...
and behind the cylinder head
Cylinder head
In an internal combustion engine, the cylinder head sits above the cylinders on top of the cylinder block. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by a head gasket...
then downward into the two internal passages leading to the carburetor
Carburetor
A carburetor , carburettor, or carburetter is a device that blends air and fuel for an internal combustion engine. It is sometimes shortened to carb in North America and the United Kingdom....
housing feeding the carburetors. The A1 had two Mikuni carburetors located on the engine's left and right sides and inline with the crankshaft
Crankshaft
The crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation...
. The carburetors were enclosed and protected from the elements by carburetor covers fixed to the crankcase
Crankcase
In an internal combustion engine of the reciprocating type, the crankcase is the housing for the crankshaft. The enclosure forms the largest cavity in the engine and is located below the cylinder, which in a multicylinder engine are usually integrated into one or several cylinder blocks...
. Inboard of each carburetor, and supporting each carburetor, was the disc cover. The rotary disc valve was housed inboard of that cover. The A1 Samurai motor was lubricated by the Superlube system, with 2-stroke oil directly injected in the intake tract.
Previously equipped with points, the ignition system
Ignition system
An ignition system is a system for igniting a fuel-air mixture. Ignition systems are well known in the field of internal combustion engines such as those used in petrol engines used to power the majority of motor vehicles, but they are also used in many other applications such as in oil-fired and...
was equipped in 1969 with a Capacitor discharge ignition
Capacitor discharge ignition
Capacitor discharge ignition or thyristor ignition is a type of automotive electronic ignition system which is widely used in outboard motors, motorcycles, lawn mowers, chainsaws, small engines, turbine-powered aircraft, and some cars...
including thyristor
Thyristor
A thyristor is a solid-state semiconductor device with four layers of alternating N and P-type material. They act as bistable switches, conducting when their gate receives a current trigger, and continue to conduct while they are forward biased .Some sources define silicon controlled rectifiers and...
-based switching system then increased the voltage to between 25,000 and 30,000 volts reducing the unburned fuel mixture within the cylinders.
This combination of displacement (247cc), CDI system, and rotary discs produced 31 hp (23.1 KW) @ 8000 RPM gave the Samurai a power-to-weight ratio of 1 horsepower per 11 pounds of weight, a 0-60 mph of 6.6 second, making the Samurai as fast or faster than production competitors in its class.
Appearance
- 1966-1967: The A1 was available with either a candy red or candy blue with chrome parts and black frame. The fuel tank had rubber knee grips, metal Kawasaki flag emblem and 2 white stripes at the bottom. Rear fender, lower rear shock absorber, chain guard, and parts of the front fork assembly were chrome. Front fender was stainless steel, a novelty then. Upper fork, headlight and speedometerSpeedometerA speedometer is a gauge that measures and displays the instantaneous speed of a land vehicle. Now universally fitted to motor vehicles, they started to be available as options in the 1900s, and as standard equipment from about 1910 onwards. Speedometers for other vehicles have specific names...
combination as well as upper rear shock absorber and side-mounted oil reservoir covers were painted.
- 1968: The color scheme remained, but the fuel tank was completely painted and a "KAWASAKI" word logo positioned at the top of the tank's panels. Upper rear shock absorbers were painted black.
- 1969: The colors remained, but the fuel tank was completely painted with oval tank sides white and a large "KAWASAKI" word logo stretching along the tank.
- 1970: The Samurai's color scheme was a pearl candy red and white. The fuel tank was red with white sides enhancing the more rectangular style shared by the Kawasaki H1 Mach IIIKawasaki H1 Mach IIIThe Kawasaki H1 Mach III was a high-performance two-stroke 500cc production motorcycle manufactured by Kawasaki Motorcycle Corporation. It was sold in the U.S. and abroad from 1969 through 1975.-History:...
. Side covers were white. The tank has a specific indentation on top.
- 1971, All Kawasaki bikes had the angular fuel tanks and fading color decal replacing the white side tank coloring. The Samurai had a white pearl color with gold/yellow/orange matrix decals. The tank is now totally flat on top.
Competitors
1969-1970 contemporaries and competitors of the A1 Samurai were:- Honda Dream CB250Honda Dream CB250The Dream CB250 was a standard motorcycle made by Honda from 1968 to 1973. It had a air-cooled parallel twin OHC four stroke engine with at 10,500 rpm. It was Honda's first 250 cc capacity motorcycle with vertical cylinders and a 5 speed transmission.-History:The CB250 was created in...
: 30 hp. 0-60 in 7.6 seconds. - Suzuki T250 Hustler. 33 hp. 0-60 mph in 7.2 seconds.
- Yamaha DS6 (250) 28 hp, 0-60 mph in 6.5 seconds.
Specifications
- Displacement: 247 cc.
- Bore and Stroke: 53.0 mm x 56.0 mm.
- Compression Ratio: 6.8:1
- Induction: 2x Mikuni Vm22mm carbs, rotary disc valve.
- Ignition: Kick start.
- Transmission: 5 Speed, wet transmission, chain driven.
- Frame: Double tubular steel cradle.
- Front Suspension: Telescopic hydraulic inner spring telescopic front fork.
- Rear suspension: Three-position spring preload adjustable shock absorber and swing arm (rear).
- Front and Rear Brakes: 180mm expanding drum.
- Top speed: 160 km/h(99 mph)
Racing
A1 Samurai have and can participate in the American Historic Racing Motorcycle AssociationAmerican Historic Racing Motorcycle Association
The American Historic Racing Motorcycle Association was formed in 1984 as a private business. In 1987 it was reorganized as a member owned non profit organization...
(AHRMA) comoetition.
Kawasaki Mach III's successfully raced with Ginger Molloy aboard his "Green Meanie" finishing 2nd just behind Giacomo Agostini's MV Agusta
MV Agusta
MV Agusta is a motorcycle manufacturer founded in 1945 near Milan in Cascina Costa, Italy. The company began as an offshoot of the Agusta aviation company formed by Count Giovanni Agusta in 1923. The Count died in 1927, leaving the company in the hands of his wife and sons, Domenico, Vincenzo,...
in the 1970 500cc World Championship. Kawasaki's