Single-cylinder engine

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DKW RT 250 (1952-1953) motorcycle engine 2007-05-20 3 DKW RT 250 in Mendig (kl).JPG
DKW RT 250 (1952–1953) motorcycle engine

A single-cylinder engine, sometimes called a thumper, is a piston engine with one cylinder. This engine is often used for motorcycles, motor scooters, go-karts, all-terrain vehicles, radio-controlled vehicles, portable tools and garden machinery (such as lawnmowers, cultivators, and string trimmers). Single-cylinder engines are made both as 4-strokes and 2-strokes.

Contents

Characteristics

Villiers engine in a 1959 Bond Minicar Bond minicar engine bay 1959.jpg
Villiers engine in a 1959 Bond Minicar

Compared with multi-cylinder engines, single-cylinder engines are usually simpler and compact. [1] Due to the greater potential for airflow around all sides of the cylinder, air cooling is often more effective for single cylinder engines than multi-cylinder engines. This reduces the weight and complexity of air-cooled single-cylinder engines, compared with liquid-cooled engines.

Drawbacks of single-cylinder engines include a more pulsating power delivery through each cycle and higher levels of vibration. [2] The uneven power delivery means that often a single-cylinder engine requires a heavier flywheel than a comparable multi-cylinder engine, resulting in relatively slower changes in engine speed. To reduce the vibration level, they often make greater use of balance shafts than multi-cylinder engines, [3] as well as more extreme methods such as a dummy connecting rod (for example the Ducati Supermono). [4] [5] These balancing devices can reduce the benefits of single-cylinder engines regarding lower weight and complexity.

Most single-cylinder engines used in motor vehicles are fueled by petrol (and use a four-stroke cycle), [6] [7] [8] however diesel single-cylinder engines are also used in stationary applications (such as the Lombardini 3LD and 15LD).

A variation known as the split-single makes use of two pistons which share a single combustion chamber.

Uses

Yamaha SRX600 (1985-1997) motorcycle engine Detail view of a large single-cylinder air-cooled motorcycle engine.jpg
Yamaha SRX600 (1985–1997) motorcycle engine

Early motorcycles, automobiles and other applications such as marine engines all tended to be single-cylinder. The configuration is almost exclusively used in portable tools, along with garden machinery such as lawn mowers. [9] Single cylinder engines also remain in widespread use in motorcycles, motor scooters, go-karts, auto rickshaws, and radio-controlled models. From 1921 to 1960, the Lanz Bulldog tractor used a large horizontally-mounted single cylinder two-stroke engine. [10] However they are rarely used in modern automobiles and tractors, due to developments in engine technology.

Single cylinder engines remain the most common engine layout in motor scooters and low-powered motorcycles. The Honda Super Cub (the motor vehicle with the highest overall sales since its introduction in 1958) uses a 49 cc (3.0 cu in) four-stroke single-cylinder engine. There are also several single-cylinder sportbikes (such as the KTM 690 Duke R), dual-sport motorcycles (such as the BMW G650GS) and the classic-styled Royal Enfield 500 Bullet. [11] [12]

The Moto3 class in the MotoGP World Championship have used four-stroke 250 cc (15.3 cu in) single cylinder engines since the class replaced 125 cc (7.6 cu in) two-strokes in 2012.

Other single-cylinder engines

Engines of other sorts, like the beam engine and certain types of Stirling engine, operate using one cylinder and thus can also be considered single-cylinder engines.

Related Research Articles

<span class="mw-page-title-main">V6 engine</span> Piston engine with six cylinders in a "V" configuration

A V6 engine is a six-cylinder piston engine where the cylinders share a common crankshaft and are arranged in a V configuration.

<span class="mw-page-title-main">V4 engine</span> Piston engine with four cylinders in "V" configuration

A V4 engine is a four-cylinder piston engine where the cylinders share a common crankshaft and are arranged in a V configuration.

<span class="mw-page-title-main">Flat-twin engine</span> Piston engine with two cylinders in opposing directions

A flat-twin engine is a two-cylinder internal combustion engine with the cylinders on opposite sides of the crankshaft. The most common type of flat-twin engine is the boxer-twin engine, where both pistons move inwards and outwards at the same time.

<span class="mw-page-title-main">Flat-four engine</span> Horizontally opposed four-cylinder piston engine

A flat-four engine, also known as a horizontally opposed-four engine, is a four-cylinder piston engine with two banks of cylinders lying on opposite sides of a common crankshaft. The most common type of flat-four engine is the boxer-four engine, each pair of opposed pistons moves inwards and outwards at the same time.

<span class="mw-page-title-main">Straight-twin engine</span> Inline piston engine with two cylinders

A straight-twin engine, also known as an inline-twin, vertical-twin, or parallel-twin, is a two-cylinder piston engine whose cylinders are arranged in a line along a common crankshaft.

<span class="mw-page-title-main">Straight-four engine</span> Inline piston engine with four cylinders

A straight-four engine is a four-cylinder piston engine where cylinders are arranged in a line along a common crankshaft.

<span class="mw-page-title-main">Straight-three engine</span> Type of engine

A straight-three engine is a three-cylinder piston engine where cylinders are arranged in a line along a common crankshaft.

Yamaha Motor Co., Ltd. is a Japanese mobility manufacturer that produces motorcycles, motorboats, outboard motors, and other motorized products. The company was established in the year 1955 upon separation from Nippon Gakki Co., Ltd. and is headquartered in Iwata, Shizuoka, Japan. The company conducts development, production and marketing operations through 109 consolidated subsidiaries as of 2012.

<span class="mw-page-title-main">Connecting rod</span> Piston engine component which connects the piston to the crankshaft

A connecting rod, also called a 'con rod', is the part of a piston engine which connects the piston to the crankshaft. Together with the crank, the connecting rod converts the reciprocating motion of the piston into the rotation of the crankshaft. The connecting rod is required to transmit the compressive and tensile forces from the piston. In its most common form, in an internal combustion engine, it allows pivoting on the piston end and rotation on the shaft end.

<span class="mw-page-title-main">Balance shaft</span> Weights used to balance otherwise unbalanced engine movement

Balance shafts are used in piston engines to reduce vibration by cancelling out unbalanced dynamic forces. The counter balance shafts have eccentric weights and rotate in opposite direction to each other, which generates a net vertical force.

<span class="mw-page-title-main">Motorcycle engine</span> Engine that powers a motorcycle

A motorcycle engine is an engine that powers a motorcycle. Motorcycle engines are typically two-stroke or four-stroke internal combustion engines, but other engine types, such as Wankels and electric motors, have been used.

Motorcycle components and systems for a motorcycle are engineered, manufactured, and assembled in order to produce motorcycle models with the desired performance, aesthetics, and cost. The key components of modern motorcycles are presented below.

<span class="mw-page-title-main">Yamaha TX500</span> Type of motorcycle

The Yamaha TX500 is a two-cylinder standard motorcycle built by Yamaha and sold in 1973 and 1974. Early models closely resembled the Triumph Bonneville in style. In 1975 the bike was renamed XS500 and then continued to be updated until 1978 when sales ended in the USA. In Europe, the model was available through 1980.

<span class="mw-page-title-main">Split-single engine</span> Type of two-stroke internal combustion engine

In internal combustion engines, a split-single design is a type of two-stroke where two cylinders share a single combustion chamber.

A big bang engine has an unconventional firing order designed so that some of the power strokes occur simultaneously or in close succession. This is achieved by changing the ignition timing, changing or re-timing the camshaft, and sometimes in combination with a change in crankpin angle. The goal is to change the power delivery characteristics of the engine. A regular firing multi-cylinder engine fires at approximately even intervals, giving a smooth-running engine. Because a big-bang engine has uneven power delivery, they tend to run rougher and generate more vibration than an even-firing engine.

Internal combustion engines come in a wide variety of types, but have certain family resemblances, and thus share many common types of components.

<span class="mw-page-title-main">Internal combustion engine</span> Engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber

An internal combustion engine is a heat engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is typically applied to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into kinetic energy which is used to propel, move or power whatever the engine is attached to.

<span class="mw-page-title-main">MV Agusta 125 Pullman</span> Type of motorcycle

The MV Agusta 125 Pullman was a motorcycle produced by the Italian manufacturer MV Agusta from 1953 to 1956. The model achieved a good sales success, and had the highest production of any machine from MV Agusta. Many brought the bike as the only means of family transport or as a work vehicle. Despite the questionable aesthetics, the Pullman offered a comfortable ride, derived by the driving position, soft suspension and large section tires. This was particularly appreciated by users, so much so that they were imitated by some competitors. 27,000 machines of this model series were produced. The model was also produced under licence in Spain by Avello, where it was marketed as the MV Avello 125 Pullman Turismo.

<span class="mw-page-title-main">Suzuki A100</span> Japanese motorcycle made beginning 1966

The Suzuki A100 is a Japanese motorcycle from the Suzuki Motor Corporation with production starting in 1966.Similar models were produced by Yamaha and Kawasaki with the YB100 & KH100 models, also with a single-cylinder two-stroke engine and rotary valve being examples.

<span class="mw-page-title-main">Royal Enfield Meteor</span> Type of motorcycle

The Royal EnfieldMeteor is an Indian cruiser-style motorcycle manufactured by Royal Enfield in India. The model was developed by engineers based at Royal Enfield’s two state-of-the-art technical centres, in Chennai. The Meteor is a direct replacement to Thunderbird 350.

References

  1. "Single Cylinder Engines". TheBikeMarket. Archived from the original on 2019-12-17.
  2. "How to Balancing a Single Cylinder Engine Crankshaft and Piston/Connecting Rod Assembly and Flywheel to Reduce Dangerous Vibration". www.gardentractorpullingtips.com. Retrieved 10 July 2019.
  3. "Engine Science: The Balancing Act of Single Cylinder Engines". www.isavetractors.com. Retrieved 10 July 2019.
  4. Methods of Balancing Single Cylinder Engines. Joseph R. Harkness. SAE Transactions. Vol. 77, Section 3: Papers 680436–680591 (1968), pp. 2329-2338
  5. Suzuki's Supermono Engine Design. A second con-rod without a piston. Ben Purvis. April 26, 2019
  6. "5 of the funkiest single-cylinder street bikes". www.motorcyclenews.com. 5 March 2009. Retrieved 7 July 2019.
  7. "The Single Life: 6 of the best thumpers". www.bennetts.co.uk. Retrieved 7 July 2019.
  8. "The 16 Best Retro Motorcycles Make Bikes Great, Again". www.thecoolist.com. 9 August 2016. Retrieved 7 July 2019.
  9. "How Car Engines Work". www.howstuffworks.com. 5 April 2000. Retrieved 10 July 2019.
  10. "The Lanz Bulldog". www.gasenginemagazine.com. December 1988. Retrieved 10 July 2019.
  11. "690 Duke: The essence of motorcycling". Archived from the original on 2012-06-12. Retrieved 2012-06-01.
  12. David Blasco. "Royal Enfield Motorcycles". Royalenfields.com. Archived from the original on 2011-12-07. Retrieved 2011-12-06.