A two-strokeengine is a type of internal combustion engine that completes a power cycle with two strokes of the piston in one revolution of the crankshaft. A four-stroke engine requires four strokes of the piston to complete a power cycle in two crankshaft revolutions. In a two-stroke engine, the end of the combustion stroke and the beginning of the compression stroke happen simultaneously, with the intake and exhaust functions occurring at the same time.
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.
A multi-valve or multivalve engine is one where each cylinder has more than two valves. A multi-valve engine has better breathing, and with more smaller valves may be able to operate at higher revolutions per minute (RPM) than a two-valve engine, delivering more power.
The Yamaha XS650 is a mid-size motorcycle that was made by the Yamaha Motor Company. The standard model was introduced in October 1969, and produced until 1979. The "Special" cruiser model was introduced in 1978 and produced until 1985. The XS650 began with the 1955 Hosk SOHC 500 twin. After about 10 years of producing 500 twin, Hosk engineers designed a 650 cc twin. Later Showa Corporation acquired the Hosk company, and in 1960 Yamaha acquired Showa, with Hosk's early design of 650 cc twin.
The Honda F-Series engine was considered Honda's "big block" SOHC inline four, though lower production DOHC versions of the F-series were built. It features a solid iron or aluminum open deck cast iron sleeved block and aluminum/magnesium cylinder head.
The two-stroke power valve system is an improvement to a conventional two-stroke engine that gives a high power output over a wider RPM range.
The Suzuki RGV250 was a Suzuki high performance sport bike which had a great number of its features and design cues based on Grand Prix technologies and ideas. It is a race-replica based on Suzuki's 250 cc (15 cu in) GP bikes from 1987 to 1998, the RGV V-2 racer. This motorcycle replaced the RG250 Gamma, which employed an alloy frame with a two-stroke parallel twin engine. The bike produced over 60 bhp in a narrow power band between 8,000 and 11,000 rpm. The dry weight ranged between 128 kg (282 lb) (1989) to 140 kg (309 lb) dry weight.
The Yamaha RZ350 is a two-stroke motorcycle produced by Japanese motorcycle manufacturer Yamaha between 1983 and 1996. Available in the US from 1983-1985, Canada until 1990 and Brazil until 1996. The RZ was the final evolution of the popular and well-known series of RD Yamaha motorcycles, and as such is also known as the RD350LC II or RD350 YPVS.
The Yamaha XS Eleven motorcycle, also called XS 1100 and XS 1.1, is a Japanese standard produced from late 1977 (MY1978) to 1983, powered by an air-cooled 1,101 cc (67.2 cu in) 4-stroke, DOHC inline four-cylinder engine mounted transversely in a duplex cradle frame with swingarm rear suspension, shaft drive, and telescopic forks.
The Yamaha FZR1000 is a motorcycle produced by Yamaha from 1987 to 1995. Classed as a sports motorcycle.
The Ducati Supersport and SS are a series of air-cooled four stroke desmodromic 2-valve 90° L-twin motorcycles made by Ducati since 1988. A limited edition Supersport called the SuperLight was sold in 1992. The name harked back to the round case 1973 Ducati 750 Super Sport, and the 1975 square case 750 and 900 Super Sport. The appellation 'SS' was applied only to the later belt drive (Pantah) based models.
The Yamaha TRX850 is a sports motorcycle with a 10-valve DOHC 849 cc 270° parallel-twin engine. First released in Japan in 1995, a version for the European market was available from 1996 to 2000.
The Yamaha V-Max, is a cruiser motorcycle produced by Yamaha from 1985 through 2020. Known for its 70° V4 engine, shaft drive, and distinctive styling, the V-Max was discontinued following the 2020 model year.
The Yamaha TDR250 was a street-legal middleweight dual-sport bike produced by Japanese motorcycle manufacturer Yamaha between 1988 and 1993.
The Yamaha RD500LC is a high-performance, two-stroke sports motorcycle, also known as the RZ500 in Canada and Australia. A lightened but detuned version known as the RZV500R was developed for the Japanese home market. Strict United States Environmental Protection Agency regulations meant that the RZ500 was not available for sale in that country. Produced for a short period between 1984 and 1986 it has become a sought after collector's machine.
The Yamaha FZ750 is a sports motorcycle produced by Yamaha Motor Corporation between 1985 and 1991. The FZ750 is notable for several reasons, perhaps the most radical being the 5-valve cylinder head with a radial arrangement. This became something of a Yamaha trademark. The FZ750 would be the first bike in the Genesis design concept.
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.
The Kawasaki KR-1 and KR-1S are road-orientated 249 cc (15.2 cu in) two-stroke sports bikes introduced between 1988 and 1992 by Kawasaki Heavy Industries.
The A7 Avenger is a 350 cc (21 cu in) Kawasaki motorcycle sold 1967 through 1971.
The Yamaha TZ 250 was a commercially available racing motorcycle with a watercooled, two-stroke, 250 cc engine produced by the Japanese manufacturer Yamaha.
