The 2si 540 and 2si 500 are a family of in-line twin-cylinder, liquid-cooled,
two-stroke
A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a power cycle with two strokes (up and down movements) of the piston during one power cycle, this power cycle being completed in one revolution of ...
, dual ignition,
aircraft engine
An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years ma ...
s that were designed for
ultralight aircraft
Ultralight aviation (called microlight aviation in some countries) is the flying of lightweight, 1- or 2-seat fixed-wing aircraft. Some countries differentiate between weight-shift control and Aircraft flight control system, conventional three-a ...
.
[Cliche, Andre: ''Ultralight Aircraft Shopper's Guide'' 8th Edition, page G-2 Cybair Limited Publishing, 2001. ]
The basic engine was originally designed and produced by
JLO-Motorenwerke of
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...
and was later acquired by the
AMW Cuyuna Engine Company
2si was an American engine manufacturer located in Beaufort, South Carolina. The company was a wholly owned subsidiary of the AMW Cuyuna Engine Company, formerly known as the ''Cuyuna Development Company''.Cliche, Andre: ''Ultralight Aircraft S ...
of
Beaufort, South Carolina
Beaufort ( , a different pronunciation from that used by the city with the same name in North Carolina) is a city in and the county seat of Beaufort County, South Carolina, United States. Chartered in 1711, it is the second-oldest city in Sou ...
and marketed under the ''Cuyuna'' brand name. Later the engine was marketed by Cuyuna under the
Two Stroke International (2si) brand. Cuyuna no longer markets engines for aircraft use although the 540 is still in production as a sport vehicle engine.
Development
The 540 is a conventional twin-cylinder engine that weighs in its L70 aircraft version. The engine features dual
capacitor discharge ignition
Capacitor discharge ignition (CDI) 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. It ...
(single in the sport vehicle version), reed valve porting, tuned exhaust system, two slide venturi-type
carburetor
A carburetor (also spelled carburettor) is a device used by an internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the venturi tube in the main meteri ...
s, liquid cooling, fuel pump, a cast iron cylinder liner, ball, needle and roller bearings throughout. The aircraft version was offered with an optional gearbox reduction system. Starting is electric starter or
recoil starter
Rope start (also called pull start or ''rewind start'') is a method of starting an internal combustion engine, usually on small machines, such as lawn mowers, chainsaws, ultralight aircraft, small outboard motors and portable engine-generators. ...
.
[Purdy, Don: ''AeroCrafter - Homebuilt Aircraft Sourcebook'', page 69. BAI Communications. ]
The 500L85 is a special engine that was developed from the 540, by reducing the cylinder bore from to . This was done to reduce the displacement to under 500 cc and allow the engine to be used for
Formula 500 auto racing.
Variants
;500L-85
:Gasoline sport vehicle engine for
Formula 500 auto racing
Auto racing (also known as car racing, motor racing, or automobile racing) is a motorsport involving the racing of automobiles for competition.
Auto racing has existed since the invention of the automobile. Races of various sorts were organise ...
. Dual carburetors, at 8000 rpm, still in production.
;540-L70
:Gasoline aircraft engine, dual carburetors, at 7000 rpm, weight , out of production.
;540L-90
:Gasoline sport vehicle engine for
auto racing
Auto racing (also known as car racing, motor racing, or automobile racing) is a motorsport involving the racing of automobiles for competition.
Auto racing has existed since the invention of the automobile. Races of various sorts were organise ...
,
kart
Kart racing or karting is a road racing variant of motorsport with open-wheel, four-wheeled vehicles known as go-karts or shifter karts. They are usually raced on scaled-down circuits, although some professional kart races are also held on ...
and
all-terrain vehicle
An all-terrain vehicle (ATV), also known as a light utility vehicle (LUV), a quad bike, or simply a quad, as defined by the American National Standards Institute (ANSI); is a vehicle that travels on low-pressure tires, with a seat that is stra ...
applications. Dual carburetors, at 8000 rpm, still in production.
Applications
;Aircraft
*
RagWing RW8 PT2S
;Automotive
*
Formula 500
Specifications (540-L70 aircraft engine)
See also
References
{{2si
Two-stroke aircraft piston engines