This article has multiple issues. Please help improve it or discuss these issues on the talk page . (Learn how and when to remove these template messages)
|
Manufacturer | Suzuki |
---|---|
Also called | Indy |
Class | Standard |
Engine | 543 cc (33.1 cu in) two-stroke triple |
Bore / stroke | 61 mm × 62 mm (2.4 in × 2.4 in) |
Compression ratio | 6.7:1 |
Top speed | 177–185 km/h (110–115 mph) claimed [1] |
Power | 37 kW (50 bhp) (claimed) [2] |
Ignition type | Battery and coil |
Transmission | Multi-disc wet clutch, 5-speed, chain drive |
Frame type | Steel double cradle |
Suspension | Front: telescopic fork, rear: swingarm |
Brakes | Drum. Front: 300 mm × 51 mm (11.8 in × 2.0 in), rear: 182 mm × 28 mm (7.18 in × 1.12 in) Starting with 1973 K model, front brake was a hydraulically operated single disk type with 290mm (11.4") diameter rotor |
Tyres | Front: 3.25-19, rear: 4.00-18 both bias ply tube type |
Wheelbase | 1,460 mm (57.5 in) |
Dimensions | W: 740 mm (29.0 in) |
Seat height | 800 mm (31.5 in) |
Weight | 211 kg (465.146 lb) [2] [3] (wet) |
Fuel capacity | 15 l; 3.3 imp gal (4.0 US gal) |
Fuel consumption | 6.5–5.3 L/100 km; 43–53 mpg‑imp (36–44 mpg‑US) [2] |
The Suzuki GT550 is a two-stroke, air-cooled, three cylinder 1970s-era motorcycle in Suzuki's "Grand Touring" GT series. Three Grand Touring models including the GT380 and GT750 and were originally offered for sale with the beginning of the 1972 model year (MY) with the 550 called "Indy" for the North American market. [4] In Suzuki's numbering scheme, automobile race tracks identify each of its 3-cylinder GT bikes for the North America market: Sebring for the 380, Indy for the 550 and Le Mans for the 750.
The 550 (and the 380) have a ram-air cooling system for the one-piece cylinder head. Two-stroke engines lose power after the engine reaches its critical temperature, so Suzuki used a system from its 500 cc two stroke twin cylinder racer, the T500. [5] This system consisted of a two piece aluminum shroud bolted to the cylinder head to duct ambient air over the cylinder head finning. The centre part of the head had an increased fin area and a larger shroud entry area in an effort to keep the centre cylinder running at the same temperature as the naturally more exposed outboard cylinders. [1]
Suzuki Recycle Injection System (SRIS) was an attempt by the manufacturer to reduce visible emissions from a two stroke motorcycle. The SRIS consisted of a small check valve in the bottom of each crank chamber along with various lengths of elastomeric tubing to the transfer ports of adjacent cylinders. See the attached diagram for a graphic depiction of the system. Two stroke engines have a tendency to collect unburnt oil and fuel in the bottom of the crank chamber at idle. Upon acceleration, after a period of idling, the unburned oil and fuel gets sucked up the transfer ports and contributes to an overrich mixture for the first 5 to 10 seconds resulting in a smokescreen from the exhaust. The SRIS plumbing routed the unburned fuel and oil to the next cylinder in the firing order thus allowing it to mix more thoroughly with the incoming charge of that cylinder and lowering the production of visible smoke. Overall fuel and oil consumption was unchanged but visible smoke was greatly reduced on sudden acceleration from rest. [6]
The exhaust itself was unusual for the time in that the centre exhaust header was split in two and exited into two mufflers much smaller than the single mufflers supplied for the two outboard cylinders. This gave a bike a balanced look with two mufflers per side. The header pipes were all joined via balance tubes, known as Exhaust Coupler Tube System (ECTS), to increase low end torque. This exhaust was continued through to the end of production for the North American market but was dropped from the M model onwards in some other markets.
Suzuki began using automatic lubrication in 1966 to eliminate premixing of oil and fuel as had been the norm for all two strokes up until then. This system was launched to eliminate mixtures with far too much oil due to the operator's unnecessary effort to preclude engine seizures. The 550 had the latest version of this multipoint oil injection called Crankcase Cylinder Injection (CCI).
The 550 was designed to be suited as a touring motorcycle with its long wheelbase and unstressed torquey engine. The engine will pull quite easily from ~3,500 RPM. The smaller bore/longer stroke dimensions allow quick burning of the air fuel mixture, allowing the use of regular grade fuel. This type of undersquare engine configuration has long since been discarded for use in street bikes by most Japanese motorcycle engine designers due to its inherent limitations on power increases and the recent advances in combustion chamber design allowing the use of large bore cylinders and high compression without detonation issues.
The GT550 introductory model was Suzuki's counter to the Kawasaki H1 Mach III. The GT550 had a massive four leading shoe double panel drum front brake shared with the GT750. The conventional telescopic front forks had rubber gaiters covering the fork stanchions. Both fenders were chromed steel. Chrome and polished aluminum were used on the rest of the bike. The fuel cap was, unusually for the times, lockable and this was carried on through to the end of production. The rear turn signal lenses were red. Engine cooling was by the Ram Air system. First year sales were 11,000+ units. [7]
A single hydraulically operated front disc brake was added in 1973. Otherwise the bike was the same as the previous model, excepting the annual paint scheme change.
Both the wheel and the other fork leg were capable of accepting another disc and caliper and a switch to a twin-disc front brake (like the GT750) was not an uncommon modification some owners made (although the larger master cylinder from the 750 was required). The single disc arrangement continued throughout the rest of the GT550's production.
The brake light operated only by the rear brake in the UK market. A switch was available as a spare part to fit onto the front brake master cylinder casting which would also operate the brake light. The necessary wiring was already included on the main wiring harness in the headlamp shell. Sales were 14,000+ in 1973. [7]
The rubber-gaiters were replaced by a cleaned up "Ceriani-style" set of forks. A touted benefit was better engine cooling but, with ram air, this was a non-issue for the most part. The three separate carburetors were replaced by three unitized rack mounted carburetors with a push-pull cable arrangement. The benefits of this were less costly carburetor balancing and more accurate fuel metering. The handlebar mounted cable operated choke was gone, replaced by a lever mounted directly on the left hand side of the carb rack. Curiously, only 2 enricheners were used leaving the right hand cylinder without one. The cylinder head and the ram air shroud were redesigned to cater for this new carb setup.
A new airbox and filter assembly had bright chrome end caps and filter servicing was easier. The frame side covers were all new as well to blend in with the lines of the airbox end caps. The chain guard was chromed steel instead of black plastic.
The instrument cluster still contained the speedometer and tachometer but a single digit LED gear indicator was added. It was in the centre of the instrument panel showing gear numbers 1 through 5 in a bright red colour. The neutral light indicator was retained as a separate item. Sales were 10,000+. [7]
In 1975, various external and internal parts of the fork were changed, the engine was re-tuned to 53 hp now with chrome bores plated directly onto the alloy barrels and the bike was heavily restyled. This type of styling ran through to the model end in 1977 with only minor changes. Problems with the starter clutch engaging while riding and thus locking up the engine were solved with the substitution of a Borg-Warner style starter clutch installed under warranty. This style of starter clutch was standard equipment on all later models. The Exhaust Coupler Tube System (ECTS) link between the exhaust pipes disappeared in some markets outside of North America. The North American area kept the exhaust coupler tubes and older engine tune of 50HP with cast iron cylinder liners through to the end of production. Available in Green in UK. This MY sales were 14,000+. [7]
In 1976 the front mudguard stay was removed. Petrol Tank Graphics swooped up at the front. Available in Red and Black. The rear shocks were stiffened. The gear indicator changed to LED segments rather than the previous dot matrix. Clock surround rubber changed from light to dark with a darker background to the clock faces This MY sales were 9,000+. [7]
The faces of the speedometer and tachometer were changed from a blue background to brown to match the appearance of the instruments on the GS models. There was also a change in the plastic used as lens because it no longer developed serious opacity and cracks after long exposure to sunlight. The instruments did not get the then-unique rose-colored backlighting that the GS models had. The front brake caliper was changed to a pivoting unit made by Asco rather than the fixed Tokico caliper that had been supplied from the introduction of the disc brake system. Rear light changed to GS style, Satin black side panels and GS style indicators
The GT and GS series were sold side by side during this one year overlap. This was the last MY for GT550 production. This MY sales were ~6,000+ making this the rarest of all the 550 models. [7]
A January 1973 Cycle World road test said the GT-550K Indy was a good compromise between the GT750 Watercooled and the GT380, with substantial enough weight and size for to long-distance touring with a passenger, and being only just light enough and narrow enough, with a 150 mm (5.8 in) ground clearance for "deft canyon road maneuvering or hustling through traffic". [2] They tested the bike's top speed at 158 km/h (98 mph) and acceleration at 0 to 60 mph (0 to 97 km/h) in 5.8 seconds or 0 to 1⁄4 mile (0.00 to 0.40 km) in 14.59 seconds at 87.8 mph (141.3 km/h). [2] Braking from 60 to 0 mph (97 to 0 km/h) was tested at 112.5 ft (34.3 m). [2]
The Suzuki GS series was Suzuki Motor Corporation's first full range of 4-stroke powered road motorcycles, having previously almost exclusively manufactured 2-stroke machines. Suzuki had produced the 4-stroke Colleda COX 125cc and 93cc 4-stroke single-cylinder machines in 1955 however the rest of Suzuki's production from 1952 to 1976 had been increasingly sophisticated two-stroke road machines, whose ultimate expression was the 750cc 3-cylinder water-cooled GT750.
The GSX Series is Suzuki's range of sport touring motorcycles powered by four-valve per cylinder four-stroke engines. The first GSX models were introduced in 1980 and represented the next step in Suzuki's four-stroke road bike range after the two-valve GS Series.
The Yamaha XS650 is a mid-size motorcycle made by Yamaha Motor Company. The standard model was introduced in October 1969,and produced through 1979. The "Special" cruiser model was introduced in 1978 and produced through 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 the Hosk company was acquired by Showa Corporation, and in 1960 Yamaha had bought Showa with Hosk's early design of 650 cc twin.
The Suzuki GSX-R750 is a sports motorcycle made by Suzuki since 1985. It was introduced at the Cologne Motorcycle Show in October 1984 as a motorcycle of the GSX-R series.
The Suzuki T20 is a motorcycle with a 247 cc (15.1 cu in), two-stroke, twin-cylinder engine, and six speed gearbox. It was first manufactured in 1965 and was produced until the end of the 1968 model year. Production peaked at more than 5000 units per month. It was superseded by an updated version which was designated the T250-1.
The L-twin is a naturally aspirated two-cylinder petrol engine by Ducati. It uses a 90-degree layout and 180-degree firing order as is mounted with one cylinder horizontal.
The Ducati SportClassics were a range of retro styled motorcycles introduced by Ducati at the 2003 Tokyo Motor Show, and put on sale in 2005 for the 2006 model year. The Paul Smart version was made for the 2006 model year only, while the Sport1000 ran from 2006 through the 2009 model years, and the GT1000 ran from the 2007 through 2010 model years.
The Suzuki GT750 is a water-cooled three-cylinder two-stroke motorcycle made by Suzuki from 1971 to 1977. It is the first Japanese motorcycle with a liquid-cooled engine. The Society of Automotive Engineers of Japan(in Japanese) includes the 1971 Suzuki GT750 as one of their 240 Landmarks of Japanese Automotive Technology.
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 Honda CB550 is a 544 cc (33.2 cu in) standard motorcycle made by Honda from 1974 to 1978. It has a four-cylinder SOHC air-cooled wet sump engine. The first version, the CB550K, was a development of the earlier CB500, and like its predecessor, had four exhaust pipes, four silencers and wire-spoked wheels.
The Kawasaki GPz750 Turbo was a sportbike manufactured from late 1983 to 1985, with two model years – the 1984 E1 and the 1985 E2. Differences were minor, a twin "push/pull" throttle cable for the E2 and different brake caliper stickers. The bike was manufactured in Japan, with parts also shipped to the US and assembled in Kawasaki's Nebraska plant for the US/Canada market to bypass the import tax levied on bikes over 700cc at the time by the US government, a protectionist move designed to save Harley-Davidson which was having financial problems at the time.
The Suzuki TU250— marketed also as the TU250X, ST250 and ST250 E-Type — is a single-cylinder, air-cooled lightweight street bike manufactured by Suzuki across two generations from 1994-2019.
BMW Motorrad is the motorcycle brand of BMW, part of its Corporate and Brand Development division. It has produced motorcycles since 1923, and achieved record sales for the fifth year in succession in 2015. With a total of 136,963 vehicles sold in 2015, BMW registered a growth of 10.9% in sales in comparison with 2014. In May 2011, the 2,000,000th motorcycle produced by BMW Motorrad was an R1200GS.
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.
The GT series is a series of two-stroke chain drive motorcycles manufactured and marketed by Suzuki for model years 1972-1977, with a range of engine capacities and cylinder counts. Certain markets received the GT380 until model year 1980.
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 Suzuki GSX-R1100 is a sport bike from Suzuki's GSX-R series of motorcycles produced from 1986 until 1998.
The Honda CB400 Super Four is a CB series 399 cc (24.3 cu in) standard motorcycle produced by Honda at the Kumamoto plant from 1992 to the present. The CB400 embodies the typical Universal Japanese Motorcycle produced through the 1970s, updated with modern technology. To this end, the bike has a naked retro design, paired with a smooth inline-four engine. Originally a Japan-only bike, it was later also available in SE Asia, and from 2008 in Australia.
The Suzuki GT250, also known as the Suzuki Hustler in the US is a 247 cc (15.1 cu in), two-stroke, twin-cylinder motorcycle produced by the Japanese Suzuki company between 1971 and 1981. The model was developed from the earlier T250, and was one of the best selling motorcycles in its class. For 1978 the bike was redesign and marketed as the GT250 X7. The X7 was capable of reaching 100 mph (160 km/h) in favourable conditions. The model range was discontinued in 1981 in favour of Suzuki's four stroke models, and the X7 was developed into the RG250 Gamma.
The Suzuki T500, variously known as the Suzuki T500/Five, Suzuki Charger, Suzuki Cobra and the Suzuki Titan during its model life, is a 492 cc (30.0 cu in), two-stroke, twin-cylinder motorcycle produced by the Japanese Suzuki company between 1968 and 1975. The model was developed as a larger version of the Suzuki T20 which was intended to compete with the large-capacity British twins in the American market. When introduced it was Suzuki's largest displacement machine. Overengineering of the engine led to the bike gaining a reputation for reliability, and being virtually bulletproof. A total of over 100,000 units were sold during the model's production.