Straight-3
Encyclopedia
Reciprocating engine
A reciprocating engine, also often known as a piston engine, is a heat engine that uses one or more reciprocating pistons to convert pressure into a rotating motion. This article describes the common features of all types...
internal combustion engine
Internal combustion engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
with three cylinder
Cylinder (engine)
A cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...
s arranged in a straight line or plane, side by side.
Most inline-three engines employ a crank angle of 120°, and are thus rotationally balanced; however, since the three cylinders are offset from each other, the firing of the end cylinders induces a rocking motion from end to end, since there is no opposing cylinder moving in the opposite direction as in a rotationally balanced straight-six engine. The use of a balance shaft
Balance shaft
In piston engine engineering, a balance shaft is an eccentric weighted shaft which offsets vibrations in engine designs that are not inherently balanced...
in an antiphase to that vibration produces a smoothly running engine.
An exception to the 120° crankshaft
Crankshaft
The crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation...
can be found in some of the inline-three engines made by motorcycle manufacturer Laverda
Laverda
Laverda was an Italian manufacturer of high performance motorcycles. The motorcycles in their day gained a reputation for being robust and innovative....
. In these engines (sometimes referred to as 180° triples), the outer pistons rise and fall together like a 360° straight-two engine. The inner cylinder is offset 180° from the outer cylinders. In these engines, cylinder #1 fires, then 180° later cylinder #2 fires, and then 180° later cylinder #3 fires. There is no power stroke on the final 180° of rotation.
Automobile use
The smallest inline-three, four-stroke automobile engine was the 543 cc SuzukiSuzuki
is a Japanese multinational corporation headquartered in Hamamatsu, Japan that specializes in manufacturing compact automobiles and 4x4 vehicles, a full range of motorcycles, all-terrain vehicles , outboard marine engines, wheelchairs and a variety of other small internal combustion engines...
F5A, which was first used in the 1979 Suzuki Alto
Suzuki Alto
The Suzuki Alto is a small car designed by Suzuki. Its selling points include low price and good fuel economy. The model was introduced in 1979 and has been built in many countries worldwide.-1st generation :...
/Fronte
Suzuki Fronte
The Fronte automobile was first introduced in March 1962 as a sedan version of the Suzulight Van. The nameplate remained in use for Suzuki's Kei car sedans until replaced by the Alto name in September 1988....
. Smart
Smart (automobile)
Smart is an automotive branch of Daimler AG. Smart is a German manufacturer of microcars produced in Hambach, France, and Böblingen, Germany...
currently produces a diminutive 799 cc inline-three diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
, the smallest automotive diesel engine yet. Most inline-three engines fall below 1.2 litre
Litre
pic|200px|right|thumb|One litre is equivalent to this cubeEach side is 10 cm1 litre water = 1 kilogram water The litre is a metric system unit of volume equal to 1 cubic decimetre , to 1,000 cubic centimetres , and to 1/1,000 cubic metre...
s, with a 1198 cc Volkswagen Group
Volkswagen Group
Volkswagen Group is a German multinational automobile manufacturing group. , Volkswagen was ranked as the world’s third largest motor vehicle manufacturer and Europe's largest....
unit seen as the largest petrol engine
Petrol engine
A petrol engine is an internal combustion engine with spark-ignition, designed to run on petrol and similar volatile fuels....
. A 1779 cc diesel engine was produced by VM Motori
VM Motori
VM Motori S.p.A. is a diesel engine manufacturing company in Cento, Italy, in Emilia-Romagna, an Italian region which is also home to Ferrari, Lamborghini, Maserati and Ducati.- History :...
to the 1984 Alfa Romeo 33 1.8 TD, the largest inline-three produced for automotive use.
Basic versions of the Suzuki Swift/Forsa and related Geo/Chevy Metro
Suzuki Cultus
The Suzuki Cultus is a supermini first presented at the 25th Tokyo Motor Show, formally introduced to the Japanese domestic market in 1983 and ultimately manufactured in seven countries across three generations and marketed worldwide under more than a dozen nameplates — prominently as the Suzuki...
used an inline-three.
Some Daihatsu cars use inline-three engines. The Charade
Daihatsu Charade
The Daihatsu Charade is a supermini which was first introduced in 1977. Daihatsu considers the Charade a "large compact" car to differentiate it from smaller compacts in its lineup, such as the Daihatsu Mira/Cuore...
and the Mira/Cuore
Daihatsu Mira
The Daihatsu Mira , is a kei car-type vehicle built by the Japanese car maker Daihatsu. It comes with a variety of options and chassis variations, with the latest variant having four models: "Mira", "Mira AVY", "Mira Gino" and "Mira VAN"...
used (or are still fitted with) this engine type. Three-cylinder 1.0 litre diesel and turbo diesel engines were also offered in Daihatsu Charades. Korean cars Daewoo Tico
Daewoo Tico
The Daewoo Tico is a city car produced by the Korean automaker Daewoo from 1991 to 2001.The Tico was based on the 1988 Suzuki Alto. The car was equipped with a three-cylinder 796 cc S-TEC engine and had a five-speed manual transmission or three-speed automatic transmission. The Tico was...
, based on the 1988 Suzuki Alto
Suzuki Alto
The Suzuki Alto is a small car designed by Suzuki. Its selling points include low price and good fuel economy. The model was introduced in 1979 and has been built in many countries worldwide.-1st generation :...
, and later base versions of Daewoo Matiz
Daewoo Matiz
-M100 :The production of Daewoo Matiz started in 1998 and it was sold in South Korea and many European markets with the code name M100. The exterior design is based on the Lucciola, a Fiat Cinquecento concept by Italdesign Giugiaro which had been rejected by Fiat. The 0.8-litre gasoline engine and...
also used inline-three 796 cc 41 hp S-TEC
Daewoo S-TEC engine
S-TEC is a low-displacement engine range codeveloped by Suzuki and Daewoo Motors for use in micro- and subcompact cars.The first model was 0.8 L Straight-3 engine, based on the powerplant of the Suzuki Alto...
petrol engine.
The Volkswagen Group
Volkswagen Group
Volkswagen Group is a German multinational automobile manufacturing group. , Volkswagen was ranked as the world’s third largest motor vehicle manufacturer and Europe's largest....
is known for using three-cylinder petrol and diesel engines; in the Audi A2
Audi A2
The Audi A2 is a Compact MPV styled five-door four- or five-seat hatchback designed supermini, produced by the German automaker Audi AG from November 1999 to 2005...
, Volkswagen Polo
Volkswagen Polo
The Volkswagen Polo is a supermini car manufactured by Volkswagen. It is sold in Europe and other markets worldwide in hatchback, saloon, coupé and estate variants....
, Volkswagen Fox
Volkswagen Fox
The Volkswagen CrossFox is a mini SUV version which sets it apart from the standard Fox. As is the case for other similar models, it is available only with front-wheel drive....
, SEAT Ibiza
SEAT Ibiza
The SEAT Ibiza is a car in the European supermini class, constructed by the Spanish car maker SEAT S.A., is SEAT's best-selling car and perhaps the most popular model in the Spanish firm's range....
and Škoda Fabia
Škoda Fabia
The Škoda Fabia is a supermini produced by Czech manufacturer Škoda Auto since 1999. It was the successor to the Škoda Felicia, which was discontinued in 2001...
. The engines in these cars range from 1.2 litre petrol with four valves
Multi-valve
In automotive engineering a multi-valve or multivalve engine is one where each cylinder has more than two valves. A multi-valve engine has better breathing and can operate at higher revolutions per minute than a two-valve engine, delivering more power.- Multi-valve rationale :A multi-valve design...
per cylinder that deliver 47 kW, to 1.4 TDI diesels= that deliver 51 kW and have turbos with variable vane geometry
Variable geometry turbocharger
Variable-geometry turbochargers are a family of turbochargers, usually designed to allow the effective aspect ratio of the turbo to be altered as conditions change. This is done because optimum aspect ratio at low engine speeds is very different from that at high engine speeds...
and deliver outstanding economy, this particular engine is used in small cars of all marques of the Volkswagen Group. The most innovative three-cylinder engine the Volkswagen Group released was the 1.2 TDI diesel, it was one of the first all-aluminium diesel engines, and at the time of release it was the lightest and most economic engine in production. It was used in the "3L" versions (from its diminutive fuel consumption of only 3 l/100 km) of the Audi A2 and the Volkswagen Lupo
Volkswagen Lupo
The Lupo is a city car manufactured by German automaker Volkswagen from 1998 to 2005.-Model history:The Lupo was introduced in 1998 to fill a gap at the bottom of the VW model range caused by the increasing size and weight of the VW Polo. Rivals included the Ford Ka, the Opel/Vauxhall Agila and...
.
Subaru
Subaru
; is the automobile manufacturing division of Japanese transportation conglomerate Fuji Heavy Industries .Subaru is internationally known for their use of the boxer engine layout popularized in cars by the Volkswagen Beetle and Porsche 911, in most of their vehicles above 1500 cc as well as...
also used an inline-three in the Subaru Justy
Subaru Justy
The Subaru Justy is a subcompact hatchback that has been sold by Japanese automobile manufacturer Subaru since 1984. From 1984–1994 Subaru manufactured the Justy itself; since then it has sold a rebadged version of other vehicles under the Justy nameplate...
and the export version of the Subaru Sambar
Subaru Sambar
The Subaru Sambar is an automobile built by automaker Subaru for the Japanese market. It is Japan's first Keitora , shorthand for "kei class truck" and is still in production. The Sambar is available in both microvan and Kei truck to fulfill the Kei car guidelines...
, called the Subaru Sumo
Subaru Sumo
The Subaru Sumo, known as the Libero in European markets apart from the UK, Norway, and Sweden, and as the Domingo in the Japanese market, was a microvan produced from 1983 to 1998. In Sweden, it was known as the Columbuss, and in Taiwan the latter generation was marketed as the Estratto...
, using their Subaru EF engine
Subaru EF engine
The EF is an automotive engine made by Subaru, introduced in 1984 for the Subaru Justy.It is a water-cooled straight-3 four-stroke engine with a belt-driven single overhead camshaft, and a chain-driven balance shaft...
.
Mitsubishi
Mitsubishi
The Mitsubishi Group , Mitsubishi Group of Companies, or Mitsubishi Companies is a Japanese multinational conglomerate company that consists of a range of autonomous businesses which share the Mitsubishi brand, trademark and legacy...
has also made extensive use of three-cylinder engines.
In the 1950s and 1960s, the Saab 93
Saab 93
The Saab 93, pronounced ninety-three, is an automobile manufactured by Saab. It was announced on August 18, 1955, and was first presented on December 1, 1955. It was styled by Sixten Sason and had a longitudinally-mounted three-cylinder 748 cc Saab two-stroke engine giving 33 hp . The...
, Saab 95
Saab 95
The Saab 95 was a 7-seater, 2-door station wagon made by Saab. Initially it was based on the Saab 93 sedan version, but the model's development throughout the years followed closely that of the 96 since the 93 was put off the market in 1960...
, Saab 96
Saab 96
For the modern car, see Saab 9-6The Saab 96 is an automobile made by Saab. It was introduced in 1960 and was produced until January 1980, a run of 20 years. Like the 93 it replaced, the 96 was a development from the old Saab 92 chassis and, on account of its improvements and modernisation, it...
, and certain Dampf-Kraft-Wagen (DKW) automobiles were powered by inline-three-cylinder, two-stroke engines. Also, the Wartburg automobiles manufactured in Eastern Germany, and FSO Syrena manufactured in Poland, used this kind of engine.
The first-generation Honda Insight
Honda Insight
The Honda Insight is a hybrid electric vehicle manufactured by Honda and the first production vehicle to feature Honda's Integrated Motor Assist system. The first-generation Insight was produced from 1999 to 2006 as a three-door hatchback...
(2000–2006) used a 1.0 litre inline-three engine in conjunction with an electric motor in its hybrid
Hybrid electric vehicle
A hybrid electric vehicle is a type of hybrid vehicle and electric vehicle which combines a conventional internal combustion engine propulsion system with an electric propulsion system. The presence of the electric powertrain is intended to achieve either better fuel economy than a conventional...
system.
Toyota, Peugeot
Peugeot
Peugeot is a major French car brand, part of PSA Peugeot Citroën, the second largest carmaker based in Europe.The family business that precedes the current Peugeot company was founded in 1810, and manufactured coffee mills and bicycles. On 20 November 1858, Emile Peugeot applied for the lion...
and Citroën
Citroën
Citroën is a major French automobile manufacturer, part of the PSA Peugeot Citroën group.Founded in 1919 by French industrialist André-Gustave Citroën , Citroën was the first mass-production car company outside the USA and pioneered the modern concept of creating a sales and services network that...
are using a common inline-three-cylinder engine in models of Aygo
Toyota Aygo
The Toyota Aygo is a city car sold by Toyota in Europe since 2005. All Aygos are built at the new factory of the Toyota Peugeot Citroën Automobile Czech joint venture in Kolin, Czech Republic. The Aygo was first displayed at the 2005 Salon de l'Automobile de Genève...
, 107
Peugeot 107
The Peugeot 107 is a city car produced by French automaker Peugeot since mid 2005.The 107 was developed by the B-Zero project of PSA Peugeot Citroën in a joint-venture with Toyota; the Citroën C1 and Toyota Aygo are badge engineered versions of the same car, although the Aygo has more detail...
and C1
Citroën C1
The Citroën C1 is a city car produced by the French manufacturer Citroën since 2005.The C1 was developed as part of the B-Zero project by PSA Peugeot Citroën in a joint-venture with Toyota. The Peugeot 107 is identical to the C1 other than the front bumper and front and rear lights, while the...
respectively.
Motorcycle use
Four-stroke
A four-stroke inline-three has been used by ApriliaAprilia
Aprilia is an Italian motorcycle company, one of the seven marques owned by Piaggio, the world's fourth largest motorcycle manufacturer.Aprilia started as a scooter manufacturer, but has more recently come to be known for its race-winning sportbikes...
, Laverda
Laverda
Laverda was an Italian manufacturer of high performance motorcycles. The motorcycles in their day gained a reputation for being robust and innovative....
, Triumph
Triumph Motorcycles Ltd
Triumph Motorcycles Ltd is the largest surviving British motorcycle manufacturer, which was established in 1984 by John Bloor after the original manufacturer Triumph Engineering went into receivership...
, Yamaha, BMW
BMW Motorrad
BMW Motorrad is the motorcycle brand of the German company BMW, part of its Corporate and Brand Development division. The current General Director of the unit is Hendrik von Kuenheim....
, Benelli
Benelli (motorcycles)
Benelli is an Italian Motorcycle manufacturer owned by Chinese company Qianjiang Group. It once manufactured shotguns, although this part of the business is now a separate company.-Early history:...
, Petronas
Petronas
PETRONAS, short for Petroliam Nasional Berhad, is a Malaysian oil and gas company that was founded on August 17, 1974. Wholly owned by the Government of Malaysia, the corporation is vested with the entire oil and gas resources in Malaysia and is entrusted with the responsibility of developing and...
, 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,...
and BSA
Birmingham Small Arms Company
This article is not about Gamo subsidiary BSA Guns Limited of Armoury Road, Small Heath, Birmingham B11 2PP or BSA Company or its successors....
.
The Triumph Rocket III
Triumph Rocket III
The Triumph Rocket III is a British three cylinder motorcycle made by the Hinckley Triumph factory and has the largest displacement engine of any mass production motorcycle , at ....
has a 2294 cc inline-three engine.
Two-stroke
Between 1972 and 1977, SuzukiSuzuki
is a Japanese multinational corporation headquartered in Hamamatsu, Japan that specializes in manufacturing compact automobiles and 4x4 vehicles, a full range of motorcycles, all-terrain vehicles , outboard marine engines, wheelchairs and a variety of other small internal combustion engines...
made three inline-three two-stroke types: the water-cooled GT750 and the air-cooled GT550 and GT380.
Between 1969 and 1978, Kawasaki triple
Kawasaki triple
The Kawasaki Triples were a range of 250 cc to 750 cc motorcycles Kawasaki exported from 1969 to 1980. The engines were air-cooled, three cylinder, two-stroke with two exhaust pipes exiting on the right side of the bike, and one on the left....
motorcycles had inline-three air-cooled engines with capacities of 250 cc, 350 cc, 400 cc, 500 cc, and 750 cc.
Non-automotive use
Inline three-cylinder engines are not limited to propelling motor vehicleMotor vehicle
A motor vehicle or road vehicle is a self-propelled wheeled vehicle that does not operate on rails, such as trains or trolleys. The vehicle propulsion is provided by an engine or motor, usually by an internal combustion engine, or an electric motor, or some combination of the two, such as hybrid...
s. The may also be used in general industrial applications. An example is the Fairbanks-Morse
Fairbanks-Morse
Fairbanks Morse and Company was a manufacturing company in the late 19th and early 20th century. Originally a weighing scale manufacturer, it later diversified into pumps, engines, windmills, locomotives and industrial supplies until it was merged in 1958...
32E14 slow-speed diesel engine which is shown coupled to a water pump.
Aviation use
The Hewland AE75Hewland AE75
The Hewland AE75 is a lightweight two stroke, inverted, inline triple, liquid-cooled aircraft engine of displacement, that was manufactured in the mid-1980s by Hewland in Maidenhead, United Kingdom.-Design and development:...
is a 750 cc lightweight two-stroke inverted three-cylinder liquid-cooled
Radiator (engine cooling)
Radiators are used for cooling internal combustion engines, mainly in automobiles but also in piston-engined aircraft, railway locomotives, motorcycles, stationary generating plant or any similar use of such an engine....
aircraft engine that produced 75 bhp, manufactured in the mid-1980s by Hewland
Hewland
Founded by Mike Hewland in 1957, Hewland is a British engineering company specialising in racing-car gearboxes. Hewland was the first company to manufacture a bespoke racing-car gearbox....
.