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62-416: The Rotax Max was introduced to karting in 1998, easy to use and very reliable, it almost immediately began to gain market share from other slower or more expensive classes. The engine is offered in different performance configurations. There are several different versions of the engine. The original has a power valve and produces around 30 hp (22 kW), and is used by racers aged 15 or older. The DD2

124-500: A Venturi tube to draw fuel into the airstream. The term "fuel injection" is vague and comprises various distinct systems with fundamentally different functional principles. Typically, the only thing all fuel injection systems have in common is a lack of carburetion . There are two main functional principles of mixture formation systems for internal combustion engines: internal mixture formation and external mixture formation. A fuel injection system that uses external mixture formation

186-405: A hot-bulb engine used a 'jerk pump' to dispense fuel oil at high pressure to an injector. Another development in early diesel engines was the pre-combustion chamber, which was invented in 1919 by Prosper l'Orange to avoid the drawbacks of air-blast injection systems. The pre-combustion chamber made it feasible to produce engines in size suitable for automobiles and MAN Truck & Bus presented

248-610: A spark plug . The Cummins Model H diesel truck engine was introduced in America in 1933. In 1936, the Mercedes-Benz OM 138 diesel engine (using a precombustion chamber) became one of the first fuel-injected engines used in a mass-production passenger car. During World War II , several petrol engines for aircraft used direct-injection systems, such as the European Junkers Jumo 210 , Daimler-Benz DB 601 , BMW 801 , and

310-451: A carburettor. Many of the carburettor's supporting components—such as the air filter, intake manifold, and fuel line routing—could be used with few or no changes. This postponed the redesign and tooling costs of these components. Single-point injection was used extensively on American-made passenger cars and light trucks during 1980–1995, and in some European cars in the early and mid-1990s. In the US,

372-581: A central injector instead of multiple injectors. Single-point injection (also called 'throttle-body injection') uses one injector in a throttle body mounted similarly to a carburettor on an intake manifold . As in a carburetted induction system, the fuel is mixed with the air before entering the intake manifold. Single-point injection was a relatively low-cost way for automakers to reduce exhaust emissions to comply with tightening regulations while providing better "driveability" (easy starting, smooth running, no engine stuttering) than could be obtained with

434-572: A fuel injection system are described in the following sections. In some systems, a single component performs multiple functions. Fuel injection is operated by spraying pressurised fuel into the engine. Therefore a device to pressurise the fuel is needed, such as a fuel pump. The system must determine the appropriate amount of fuel to be supplied and control the fuel flow to supply this amount. Several early mechanical injection systems used relatively sophisticated helix-controlled injection pump(s) that both metered fuel and created injection pressure. Since

496-705: A fuel injection system in 1941 and by 1956 it was used in the Jaguar racing cars. At the 1957 24 Hours of Le Mans , the 1st to 4th placed cars were Jaguar D-Type entries using a Lucas fuel injection system. Also in 1957, General Motors introduced the Rochester Ramjet option, consisting of a fuel injection system for the V8 engine in the Chevrolet Corvette. During the 1960s, fuel injection systems were also produced by Hilborn , SPICA and Kugelfischer . Up until this time,

558-405: A mechanical power valve which is activated at RPM speed. The YPVS is only found on the liquid-cooled bikes not air cooled versions. Yamaha have also used a guillotine version in some of their later models such as the 1994 TZR250 3XV SP model, and many later TZ road race bikes. The TZR250R 3XV SPR actually uses a Triple-YPVS, which is a combination of the guillotine and "cotton reel" designs. Yamaha

620-573: A passenger car was released the following year, in the Mercedes-Benz 300SL sports car. However the engine suffered lubrication problems due to petrol diluting the engine oil, and subsequent Mercedes-Benz engines switched to a manifold injection design. Likewise, most petrol injection systems prior to the 2000s used the less-expensive manifold injection design. Throughout the 1950s, several manufacturers introduced their manifold injection systems for petrol engines. Lucas Industries had begun developing

682-477: A pulsed flow system which used an air flow meter to calculate the amount of fuel required. L-Jetronic was widely adopted on European cars during the 1970s and 1980s. As a system that uses electronically-controlled fuel injectors which open and close to control the amount of fuel entering the engine, the L-Jetronic system uses the same basic principles as modern electronic fuel injection (EFI) systems. Prior to 1979,

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744-409: A road/commuter bike, the limited power range is a problem. To provide more low RPM power, as well as enable the engine to produce a lot of high RPM power, a power valve system is used. All power valve systems vary the duration of the exhaust port open time, which gives the engine usable low end power combined with excellent top end power. Manufacturers have also included sub exhaust chambers that extend

806-446: A single (engine) brand race series for the MAX engine concept - called Rotax Max Challenge . This race series is organized in various classes (125 Micro MAX, 125 Mini MAX, 125 Junior MAX, 125 MAX and 125 MAX DD2) in around 60 countries. Competitors from the national Rotax Max Challenges in the 125 Junior MAX, 125 MAX and 125 MAX DD2 class can qualify to participate at the annual Grand Finals of

868-399: A sophisticated common-rail injection system. The latter is the most common system in modern automotive engines. During the 20th century, most petrol engines used either a carburettor or indirect fuel injection. Use of direct injection in petrol engines has become increasingly common in the 21st century. In a common rail system, fuel from the fuel tank is supplied to a common header (called

930-516: A two-blade exhaust valve (using over 50 parts) The "V-TACS" - Variable Torque Amplification Chamber System - works differently from the "ATAC system" and it will only work when it is used in conjunction with a tuned muffler. Tuned mufflers/expansion chambers increase power but only at the RPM they are designed for and can actually cause a power loss outside their tuned RPM. "V-TACS system" takes advantage of using an expansion chamber without losing power outside

992-413: Is always intermittent (either sequential or cylinder-individual). This can be done either with a blast of air or hydraulically, with the latter method being more common in automotive engines. Typically, hydraulic direct injection systems spray fuel into the air inside the cylinder or combustion chamber. Direct injection can be achieved with a conventional helix-controlled injection pump, unit injectors, or

1054-423: Is an improvement to a conventional two-stroke engine that gives a high power output over a wider RPM range. A stroke is the action of a piston travelling the full length of its cylinder . In a two-stroke engine, one of the two strokes combines the intake stroke and the compression stroke , while the other stroke combines the combustion stroke and the exhaust stroke . As the piston travels upward in

1116-541: Is another fully powered version which has two gears and is direct drive in that the axle goes through the engine without need for a chain. 125 MAX EVO "base" configuration: 125 Junior MAX configuration: 125 Mini MAX engine configuration: 125 Micro MAX engine configuration: Based on an evolution concept, each of the above configurations can be upgraded or downgraded to any of the other configurations by replacing various accessories and components. 125 MAX DD2 engine configuration: BRP-Powertrain has introduced

1178-546: Is called a manifold injection system. There exist two types of manifold injection systems: multi-point injection (or port injection) and single-point injection (or throttle body injection). Internal mixture formation systems can be separated into several different varieties of direct and indirect injection, the most common being the common-rail injection system, a variety of direct injection. The term "electronic fuel injection" refers to any fuel injection system controlled by an engine control unit . The fundamental functions of

1240-533: Is injected at the same time to all the cylinders; or cylinder-individual , in which the engine control unit can adjust the injection for each cylinder individually. Multi-point injection (also called 'port injection') injects fuel into the intake ports just upstream of each cylinder's intake valve , rather than at a central point within an intake manifold. Typically, multi-point injected systems use multiple fuel injectors, but some systems, such as GM's central port injection system, use tubes with poppet valves fed by

1302-548: The Shvetsov ASh-82FN (M-82FN) . The German direct-injection systems were based on diesel injection systems used by Bosch, Deckel, Junkers and l'Orange. By around 1943, the Rolls-Royce Merlin and Wright R-3350 had switched from traditional carburettors to fuel-injection (called "pressure carburettors" at the time), however these engines used throttle body manifold injection , rather than the direct-injection systems of

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1364-475: The Wankel engine . In a manifold injection system, air and fuel are mixed outside the combustion chamber so that a mixture of air and fuel is sucked into the engine. The main types of manifold injections systems are multi-point injection and single-point injection . These systems use either a continuous injection or an intermittent injection design. In a continuous injection system, fuel flows at all times from

1426-669: The accumulator ), and then sent through tubing to the injectors, which inject it into the combustion chamber. The accumulator has a high-pressure relief valve to maintain pressure and return the excess fuel to the fuel tank. The fuel is sprayed with the help of a nozzle that is opened and closed with a solenoid-operated needle valve . Third-generation common rail diesels use piezoelectric injectors for increased precision, with fuel pressures up to 300  MPa or 44,000  psi . The types of common-rail systems include air-guided injection and spray-guided injection . Used by diesel engines, these systems include: This injection method

1488-437: The throttle body . Fuel injectors which also control the metering are called "injection valves", while injectors that perform all three functions are called unit injectors . Direct injection means that the fuel is injected into the main combustion chamber of each cylinder. The air and fuel are mixed only inside the combustion chamber. Therefore, only air is sucked into the engine during the intake stroke. The injection scheme

1550-456: The "AETC system." A small computer monitors engine RPM and adjusts a two-blade exhaust valve with an electric servo. Honda equipped many two-stroke motorcycles such as the NSR125 and NSR250 models with RC - Valve power plants. Kawasaki uses a power-valve system called KIPS (Kawasaki Integrated Power Valve System) on their two-stroke bikes. The KIPS utilizes both alterations in port height, closing of

1612-407: The 'tuned length' of the expansion chamber. Power valve actuation can be by mechanical (RPM dependent) or electric (servo motor) means increasingly with electronic control. Electronic control offers a greater degree of accuracy as well as being able to vary the opening of the valve and be tuned to conditions. AETC and Super AETC Suzuki engines, Automatic Exhaust Timing Control: The two-blade version

1674-549: The 1950 Goliath GP700 small saloon, it was also added to the Gutbrod Superior engine in 1952. This mechanically-controlled system was essentially a specially lubricated high-pressure diesel direct-injection pump of the type that is governed by the vacuum behind an intake throttle valve. A Bosch mechanical direct-injection system was also used in the straight-eight used in the 1954 Mercedes-Benz W196 Formula One racing car. The first four-stroke direct-injection petrol engine for

1736-428: The 1954-1959 Mercedes-Benz 300 SL - all used manifold injection (i.e. the injectors located at the intake ports or throttle body, instead of inside the combustion chamber). This began to change when the first mass-produced petrol direct injection system for passenger cars was a common rail system introduced in the 1997 Mitsubishi 6G74 V6 engine. The first common-rail system for a passenger car diesel engine

1798-452: The 1980s, electronic systems have been used to control the metering of fuel. More recent systems use an electronic engine control unit which meters the fuel, controls the ignition timing and controls various other engine functions. The fuel injector is effectively a spray nozzle that performs the final stage in the delivery of fuel into the engine. The injector is located in the combustion chamber , inlet manifold or - less commonly -

1860-571: The Electrojector system, becoming the first cars known to use an electronic fuel injection (EFI) system. The Electrojector patents were subsequently sold to Bosch, who developed the Electrojector into the Bosch D-Jetronic . The D-Jetronic was produced from 1967-1976 and first used on the VW 1600TL/E . The system was a speed/density system, using engine speed and intake manifold air density to calculate

1922-497: The G10 engine in the 2000 Chevrolet Metro became the last engine available on an American-sold vehicle to use throttle body injection. In indirect-injected diesel engines (as well as Akroyd engines), there are two combustion chambers: the main combustion chamber, and a pre-chamber (also called an ante-chamber) that is connected to the main one. The fuel is injected only into the pre-chamber (where it begins to combust), and not directly into

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1984-600: The German engines. From 1940, the Mitsubishi Kinsei 60 series engine used a direct-injection system, along with the related Mitsubishi Kasei engine from 1941. In 1943, a low-pressure fuel injection system was added to the Nakajima Homare Model 23 radial engine. The first mass-produced petrol direct-injection system was developed by Bosch and initially used in small automotive two-stroke petrol engines. Introduced in

2046-460: The RZ/RD350 YPVS (LC2-onwards), and RZ/RD500 GP Replica in 1983–84. ATAC System: The Honda Automatic Torque Amplification Chamber system works by effectively increasing or decreasing the volume of the exhaust system with a small butterfly valve located just before the exhaust connection. At low RPM a centrifugal crankshaft driven gear opens the valve into a small chamber and increases the volume of

2108-473: The Rotax Max Challenge, where most of the costs are covered by BRP-Powertrain. To assure the equal performance of the engines, BRP-Powertrain has established a very strict technical regulation and a sealing system for the engines. Only official service centers are authorized to check engines for their conformity and to seal them. Two-stroke power valve system The two-stroke power valve system

2170-571: The amount of fuel to be injected. In 1974, Bosch introduced the K-Jetronic system, which used a continuous flow of fuel from the injectors (rather than the pulsed flow of the D-Jetronic system). K-Jetronic was a mechanical injection system, using a plunger actuated by the intake manifold pressure which then controlled the fuel flow to the injectors. Also in 1974, Bosch introduced the L-Jetronic system,

2232-551: The bottom of the power stroke, the transfer ports, which deliver fresh fuel-air mixture, are open at the same time as the exhaust port. This can allow a significant amount of fresh fuel to run straight through the engine without being burned in the process of power production. Properly designed exhaust systems help minimize the amount of raw fuel loss in the exhaust process, but a carbureted two-stroke engine will always waste some fuel (modern direct injected engines avoid this). Many producers of two-stroke performance bikes fit them with

2294-434: The cylinder above the piston. Once the piston reaches the bottom of the stroke, the second stroke is completed and the process is repeated. The only moving parts inside simple two-stroke engines are the crankshaft, the connecting rod, and the piston. It is the same simplicity in design, however, that causes a two-stroke engine to be less fuel-efficient and produce high specific levels of undesirable exhaust gas emissions. At

2356-400: The cylinder, it creates low pressure area in the crankcase ; this draws fresh air and atomized fuel from the carburetor through a hole in the cylinder wall or directly into the crankcase. As the piston continues travelling upward, transfer ports and the exhaust ports are closed off, thus trapping the combustible mixture in the combustion chamber. As the piston reaches the top of the cylinder,

2418-564: The diesel engine, but also improved it. He increased the air blast pressure from 4–5 kp/cm (390–490 kPa) to 65 kp/cm (6,400 kPa). In the meantime, the first manifold injection system was designed by Johannes Spiel in 1884, while working at Hallesche Maschinenfabrik in Germany. In 1891, the British Herbert-Akroyd oil engine became the first engine to use a pressurised fuel injection system. This design, called

2480-411: The electronics in fuel injection systems used analogue electronics for the control system. The Bosch Motronic multi-point fuel injection system (also amongst the first systems where the ignition system is controlled by the same device as the fuel injection system) was the first mass-produced system to use digital electronics . The Ford EEC-III single-point fuel injection system, introduced in 1980,

2542-663: The entire rev range, so it was that the YPVS was born. The valve is of a cylindrical "cotton reel" design running across the top of the exhaust port, it is turned by a servo motor controlled from a control box taking information from the CDI (and other locations). The valve is a slightly oval shape. This changes the height and size of the exhaust port at different engine speeds, maximizing the available power at all rev ranges, opening up firstly at 3k rpm for low end power, gradually in between 3-6k, fully opening at 6k rpm for maximum power, on most 125cc. It

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2604-506: The exhaust by allowing the exhaust gases to flow through the chamber. At high RPM the ATAC valve is closed and the exhaust simply exits into the expansion chamber. A larger expansion chamber allows for more power at lower RPMs because of the extra time needed for the impulse to "bounce" back for the supercharger effect. It was used on their CR motocrossers, GP bikes and MTX, MVX, NS and NSR road bikes. HPP valve. A centrifugal governor opens and closes

2666-462: The exhaust port. This system is recognizable by a small box above the exhaust outlet; the power-valves are situated in this box. Depending on the valve, they may be made of two (older version) or three (newer version) separate blades. YPVS Yamaha engines, Yamaha Power Valve System: Yamaha engineers realized that by altering the height of the exhaust port they could effectively change the engine power delivery thereby having optimal power and torque across

2728-413: The exhaust power valve systems. These valves act to vary the height (and width) of the exhaust port thereby broadening power delivery over a wider rev range. Exhaust ports with fixed dimensions only produce usable power in a narrow rev range, which also affects fuel consumption and emissions. In a race bike, this is not a problem as the engine will be operating at high RPM almost all the time. However, in

2790-402: The expansion chamber's tuned RPM. Within the head and cylinder of the engine, there is a chamber that is sealed by a valve. This sealed chamber is vented onto the exhaust port when the valve is open. At low RPM this valve is open, this has the effect of increasing the exhaust manifold volume and negating the power loss that would normally be apparent at low RPM with an expansion chamber. At mid RPM

2852-441: The first direct-injected diesel engine for trucks in 1924. Higher pressure diesel injection pumps were introduced by Bosch in 1927. In 1898, German company Deutz AG started producing four-stroke petrol stationary engines with manifold injection. The 1906 Antoinette 8V aircraft engine (the world's first V8 engine) was another early four-stroke engine that used manifold injection. The first petrol engine with direct-injection

2914-405: The flow of burned fuel into the expansion chamber or muffler . The piston then moves downward, where the air-fuel mixture remains from the previous intake-compression stroke. Shortly after the exhaust port is uncovered by the downward travel of the piston, the transfer ports begin to be uncovered. The transfer ports act as a passage through which the air-fuel mixture moves from the crankcase into

2976-631: The fuel injection systems had used a mechanical control system. In 1957, the American Bendix Electrojector system was introduced, which used analogue electronics for the control system. The Electrojector was intended to be available for the Rambler Rebel mid-size car, however reliability problems meant that the fuel injection option was not offered. In 1958, the Chrysler 300D , DeSoto Adventurer , Dodge D-500 and Plymouth Fury offered

3038-572: The fuel injectors, but at a variable flow rate. The most common automotive continuous injection system is the Bosch K-Jetronic system, introduced in 1974 and used until the mid-1990s by various car manufacturers. Intermittent injection systems can be sequential , in which injection is timed to coincide with each cylinder's intake stroke; batched , in which fuel is injected to the cylinders in groups, without precise synchronization to any particular cylinder's intake stroke; simultaneous , in which fuel

3100-501: The late 1930s and early 1940s, being the first fuel-injected engines for passenger car use. In passenger car petrol engines, fuel injection was introduced in the early 1950s and gradually gained prevalence until it had largely replaced carburetors by the early 1990s. The primary difference between carburetion and fuel injection is that fuel injection atomizes the fuel through a small nozzle under high pressure, while carburetion relies on suction created by intake air accelerated through

3162-503: The main combustion chamber. Therefore, this principle is called indirect injection. There exist several slightly different indirect injection systems that have similar characteristics. Types of indirect injection used by diesel engines include: In 1872, George Bailey Brayton obtained a patent on an internal combustion engine that used a pneumatic fuel injection system, also invented by Brayton: air-blast injection . In 1894, Rudolf Diesel copied Brayton's air-blast injection system for

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3224-427: The means of a fuel injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All compression-ignition engines (e.g. diesel engines ), and many spark-ignition engines (i.e. petrol (gasoline) engines , such as Otto or Wankel ), use fuel injection of one kind or another. Mass-produced diesel engines for passenger cars (such as the Mercedes-Benz OM 138 ) became available in

3286-406: The mixture in the cylinder is compressed to the point of ignition . The second stroke begins once ignition has taken place. The power stroke begins after the air-fuel mixture is ignited. The burnt fuel creates pressure in the cylinder above the piston and forces it downward. As the piston passes the midpoint of the downstroke, the exhaust port to the side of the cylinder is uncovered and initiates

3348-438: The secondary port ducting, and a resonant chamber. KIPS is operated by a mechanical governor on single cylinder machines. The twin cylinder and newer single cylinder model bikes have an electric motor transferring movement via cable and linkages called HI-KIPS. Fuel injection#Direct injection systems Fuel injection is the introduction of fuel in an internal combustion engine , most commonly automotive engines , by

3410-490: The valve is closed, this enables the expansion chamber to work. It is identified by the head and cylinder, being much larger than normal for its displacement, the cylinder wall is also cast with the wording VTACS on it. V-TACS was a foot-operated power valve system made by Honda on some of its small two-stroke bikes and scooters, like the Honda FC50 . The Honda Revolution Control valve is designed and works in principle like

3472-424: Was a two-stroke aircraft engine designed by Otto Mader in 1916. Another early spark-ignition engine to use direct-injection was the 1925 Hesselman engine , designed by Swedish engineer Jonas Hesselman. This engine could run on a variety of fuels (such as oil, kerosene, petrol or diesel oil) and used a stratified charge principle whereby fuel is injected towards the end of the compression stroke, then ignited with

3534-476: Was actually the first company to produce consistent results with their YPVS in their race bikes. The 1977 OW35K was the first race bike to incorporate the power valve system and it won the Finnish GP in 1977. The Kadenacy effect was harnessed and controlled to a point that gave Yamaha great advantage over all the other manufacturers throughout the late '70s and into the mid '80s. The first street bikes with YPVS were

3596-407: Was another early digital fuel injection system. These and other electronic manifold injection systems (using either port injection or throttle-body injection ) became more widespread through the 1980s, and by the early 1990s they had replaced carburettors in most new petrol-engined cars sold in developed countries. The aforementioned injection systems for petrol passenger car engines - except for

3658-648: Was fitted to all of the later models of the RZ/RD two-stroke road bikes (125, 250, 350 and 500 cc), the TZR range. It was also added to the DT(125lc 2/3) range after 1984 (but was locked closed to comply with UK learner regulations until the (R) in 1988-04 which had a fully functional YPVS valve) the DT125R has a better design of engine, although not much altered in speed, just more reliable than its predecessor. The YZ series of motocross bikes has

3720-580: Was fitted to the VJ21 RGV250, and the three-blade version, to the VJ22 RGV250 and Suzuki RG150 . With the AETC system, the power-valve systems are normally partially closed at low RPM; when closed, it enables the engine to make more power. Up to a certain point, however, power drops off as the engine is unable to expel enough gases out of the exhaust. When the power-valve is opened, it allows more gases to flow out of

3782-449: Was previously used in many diesel engines. Types of systems include: The M-System , used in some diesel engines from the 1960s to the 1980s, sprayed the fuel onto the walls of the combustion chamber, as opposed to most other direct-injection systems which spray the fuel into the middle of the chamber. Manifold injection systems are common in petrol-fuelled engines such as the Otto engine and

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3844-466: Was the Fiat Multijet straight-four engine, introduced in the 1999 Alfa Romeo 156 1.9 JTD model. Since the 2010s, many petrol engines have switched to direct-injection (sometimes in combination with separate manifold injectors for each cylinder). Similarly, many modern diesel engines use a common-rail design. Stratified charge injection was used in several petrol engines in the early 2000s, such as

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