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Motorcycles have been around for more than ten decades. During this time, motorcycle engines have developed through tweaking and reworking items to get the best performance. There have been more than one dozen engines, but some never met with success. Cost efficiency and customer satisfaction brought failure to a number of motorcycle engines.

All motorcycle engines are fueled by gasoline. To best understand engine types, it is important to understand how an engine works.

A pole called a rod cranks inside the engine and creates a draft that pulls both gasoline and air into a chamber called the cylinder. Inside the cylinder, a piston and rod quickly move up to push the gasoline and air into a smaller space where it meets the spark plug. The spark plug produces a spark between its two metal pieces.

Once the spark plug gives off a spark, the gasoline and air explode. This pushes the piston down, which in turn drives the belt or chain. This action is called torque. The movement of the belt or chain causes the rear wheel of the motorcycle to revolve. A motorcycle’s performance is determined by how many cylinders are inside the engine and how they are arranged.

Single cylinder engine:

A single cylinder engine has one cylinder and one piston. Single cylinder engines are used in all off road motorcycles. The single cylinder provides a lot of torque, but also a load of vibration. The vibration is loud and one of the qualities that dirt bike race fans crave during a race.

Twin cylinder engine:

Logically, twin cylinder engines have two cylinders. The cylinders are placed together at an angle. Usually the cylinders are positioned at a 90 degree angle, but there are exclusions to that standard. A twin cylinder engine produces more power because there is more torque and more fuel used. Twin cylinder engines do not vibrate as much as a single cylinder engine.

Now, as stated above, there are exceptions. The boxed or boxer design finds cylinders placed side by side. This produces even less vibration, but adds a new issue. The cylinders tend to jut out the side of the bike, which makes it hard to take sharp corners. Another issue is the tremendous heat that the cylinders project; it makes leg protection a necessary evil.

Triple Cylinder Engines

A three cylinder engine finds the cylinders included in a head. This type of engine offers a load of power, but it also requires more parts. Each cylinder requires an additional fuel injector and carburetor. The more cylinders included on an engine, the higher the engine RPM. More RPM means more power. Triumph makes motorcycles using three cylinders and boy can they fly!

Four Cylinder Engines

The four cylinder engine is just like the three cylinder engine only it has the additional cylinder and therefore weighs more. As is true of any engine, more cylinders equal more power and smoother sailing.

It is important to consider how much size and power you require in your motorcycle. If you are taking your bike off road, you need a bike with plenty of torque and a low rpm to make it up hills and quickly navigate corners. For off roading, stick with a single cylinder. A double cylinder is your second choice.

If your main purpose for riding a motorcycle is riding through traffic and along roads, do not purchase a bike with less than a twin cylinder engine, although a three or four cylinder engine is a better idea.

A decade ago motorcycles had speed, looks, and style. They have certainly improved with each passing year. Year after year motorcycle manufacturers get more innovative, produce faster, lighter and more comfortable motorcycles, and learn what works and what doesn’t. What are the favorites from 2007?

- Yamaha V Star 1300 Tourer.

These motorcycles have a V2 engine with an electric starter and a liquid cooling system. The seat was 28.1 inches and the dry weight was 668 pounds. It was made with a double cradle frame and a telescopic fork front suspension with a swingarm rear suspension. These motorcycles had single disc rear brakes and double disc front brakes. They have a fuel capacity of 4.88 gallons.

- BMW R1200GS

These motorcycles have a two cylinder boxer engine. They also have an electronic fuel injection with an electric starter. These motorcycles had oil and air cooled engines and a 6-speed gearbox. At 438 pounds, they were meant for speed. These off road motorcycles came in desert yellow metallic, rock red metallic, ocean blue metallic, or granite gray metallic. Though the fuel capacity is a whopping 5.28 gallons, the consumption is 1.45 gallons for every 6.2 miles.

- Yamaha WR 450 F

These are also off road motorcycles. They have a single cylinder engine, with a liquid cooling system. At just 246 pounds, it is nearly two-thirds the weight of the BMW R1200GS motorcycles. The front suspension is a telescopic fork, the rear a swingarm. The fuel capacity on these motorcycles is a mere 2.10 gallons. These motorcycles had single disc brake systems for both front and rear.

- Yamaha FZ1 Fazer

These naked motorcycles had in line four engines with an electric starter. They also had a liquid cooling system, a final drive chain transmission, and digital ignition. Like the BMW R1200GS, these Yamaha motorcycles weighed 438 pounds. The frame was aluminum die cast and the front suspension was telescopic upside down forks. The rear a swingarm suspension. These motorcycles had double disc front brakes and single disc rear brakes. Fuel capacity on these motorcycles is 4.76 gallons.

- Harley Davidson VRSCX

These custom or cruiser motorcycles have a V2 engine. They have an electronic sequential port fuel injection system and liquid cooling system. The seat is a mere 27.1 inches high and the weight 637 pounds. These motorcycles are 5-speed with a final drive belt transmission. The front and rear brakes are both single disc four piston. These motorcycles came in two tone mirage orange pearl or brilliant silver pearl. It has a 5 gallon fuel capacity.

- Victory Vegas Jackpot

Like the Harley Davidson VRSCX, these motorcycles are also custom or cruiser motorcycles. With a V2 engine, an air cooling system, and final drive belt transmission, it has many of the same features as the Harley Davidson VRSCX motorcycles. It has an electronic fuel injection system and a 6-speed gearbox. These motorcycles had an even shorter seat at 25.7 inches high. Though the seat was lower, they were a bit heavier weighing 659 pounds. The fuel capacity was 4.5 gallons and colors included black, orange crush, or sunset red.

Ever since 1932 BMW has been making motorcycles that fall in the high-end class and that are regarded as being amongst the highest quality motorcycles.

They are known for excellence and for providing some of the most enjoyable motorcycle rides around.

BMW first introduced the R32 BMW motorcycle in 1932 and have been developing that particular style of motorcycle into something that has fan clubs all over the world.

This first BMW motorcycle had a peculiar engine, known as the “boxer twin” engine. It was designed for air cooling and its two cylinders protruded from opposite sides of the motorcycle.

Later during the BMW motorcycle development they also developed more traditional four cylinder motorcycle models.

Not only did BMW manufacture road bikes, they also branched out into off-road motorcycles and have made a name for themselves there as well.

Apart from the association with quality through the BMW logo and name, BMW motorcycles also attract loyal fans because the motorcycles give comfortable rides without sacrificing sportiness and performance.

Apart from some of its off-road models, the BMW motorcycle generally is a big motorcycle. However, drivers of these motorcycles will tell you that they handle like a dream.

Today they are four different series of BMW motorcycles. These are the F, G, R, and K series.

The F series has a four stroke, four valve engine and has a chain drive to the back wheel. The G series is an off-road motorcycle that BMW developed in conjunction with Aprilia. The R series motorcycles still have their trademark protruding cylinder heads but they have been improved upon over earlier models. The K series has also been developed into a motorcycle technological wonder. Both the R and K motorcycle series come with powerful engines that can drive a small car.

If comfort, style, technology, and stylishness appeal to you in motorcycles, then the BMW motorcycle will definitely be on your shopping list. On the one hand they come with a high price tag, but on the other hand you know that you are buying BMW quality, comfort, and style.

The Chevrolet Corvair engine was a flat-6 (or boxer engine) piston engine used exclusively in the 1960s Chevrolet Corvair automobile. It was a highly unusual engine for General Motors: It was air-cooled, used a flat design, with aluminum heads (incorporating integral intake manifolds) and crankcase, and individual iron cylinder barrels. The heads were modeled after the standard Chevrolet overhead valve design, with large valves operated by rocker arms, actuated by pushrods run off a nine lobe camshaft (exhaust lobes did double duty for two opposing cylinders) running directly on the crankcase bore without an inserted bearing, operating hydraulic valve lifters (which eliminated low temperature valve clatter otherwise seen with that much aluminum in the engine, due to its high degree of thermal expansion).

The flat horizontally opposed (“flat engine”) air-cooled engine design, previously used by Volkswagen and Porsche as well as Lycoming aircraft engines, offered many advantages. Unlike inline or V designs, the horizontally opposed design made the engine inherently mechanically balanced, so that counterweights on the crankshaft were not necessary, reducing the weight greatly. Eliminating a water-cooling system further reduced the weight, and the use of aluminum for the heads and crankcase capitalized on this weight reduction; so that with the use of aluminum for the transaxle case, the entire engine/transaxle assembly weighed under 500 pounds (225 kilograms). In addition, the elimination of water-cooling eliminated several points of maintenance and possible failure, reducing them all to a single point; the fan belt. As with the Volkswagen and Porsche designs, the low weight and compact but wide packaging made the engine ideal for mounting in the rear of the car, eliminating the weight and space of a conventional drive shaft.

Two years after its 1960 debut, the Corvair engine gained another unusual attribute: it was the second production engine ever to be equipped from the factory with a turbocharger, released shortly after the Oldsmobile Jetfire V8.

Aircraft hobbyists and small volume builders, perhaps seeing the Corvair engine’s similarity to Lycoming aircraft engines, very quickly began a cottage industry of modifying Corvair engines for aircraft use, which continues to this day. The Corvair engine also became a favorite for installation into modified Volkswagens and Porsches, as well as dune buggies and homemade sports and race cars.

140

The Corvair’s innovative turbocharged engine; The turbo, located at top right, takes in air through the large air cleaner at top left, passes it through the side draft carburetor in between, and feeds pressurized fuel/air mixture into the engine through the chrome T-tube visible spanning the engine from left to right.

The Corvair’s innovative turbocharged engine; The turbo, located at top right, takes in air through the large air cleaner at top left, passes it through the sidedraft carburetor in between, and feeds pressurized fuel/air mixture into the engine through the chrome T-tube visible spanning the engine from left to right.

The initial Corvair engine displaced 140 in³ (2.3 L) and produced 80 hp (60 kW). The high performance optional “Super TurboAir” version, introduced mid 1960 with a special camshaft and revised carburetors and valve springs produced 95 hp (70 kW).

145

In 1961, the engine received its first increases in size via a larger bore. The engine was now 145 in³ and the base engine was said to produce the same 80 hp (60 kW). The new high performance engine was rated at 98 hp (73 kW). In 1962 the high performance engine was rated at 102 hp (76 kW). The high compression 102 HP heads were added to the Monza models equipped with Powerglide when the standard engine was ordered, giving an 84 HP engine rating. 1962 engines returned to automatic chokes after a one year only manual choke on 1961 models.

The ultimate performance was found in the Spyder model, which became available with a turbocharged engine rated at 150 hp (112 kW). The turbocharger was mounted on the right side of the firewall behind the rear seat, fed by both exhaust manifolds; a single sidedraft carburetor mounted on the left side of the firewall fed directly into the turbocharger’s intake, with a chromed pipe leading from the turbocharger’s outlet to what would otherwise be the carburetor mounting pads on the intake manifolds, which were integral parts of the heads. The turbocharged heads received some valve upgrades to improve durability. Exhaust valves on turbocharged engines were made from a non-ferrous material used in jet engine turbine buckets, called ‘Nimonic 80-A’. All other Corvair engines had slight upgrades in valve and valve seat materials as well for 1962.

164

The engine was stroked out (from 2.6″ to 2.94″) displacing 164 in (2.7 L) for 1964. Power output was boosted to 95 hp (70 kW) for the base model and 110 hp (80 kW) in the high performance normally aspirated engine, while the Turbocharged engine remained rated at 150 hp for this year. This increase in stroke was the maximum the engine could tolerate, to the point that the bottoms of the cylinder barrels had to be notched to clear the big end of the connecting rods.

For the 1965 model year, all engines had the head gasket area between the cylinder and the head widened, with a new design folded “Z” section stainless steel head gasket virtually eliminating any risk of head gasket failure. A 140 hp (104 kW) version with 4 single barrel carburetors, and a progressive linkage was introduced in 1965 as option L63 ‘Special High Performance Engine’ and was standard equipment on the Corsa model. The carburetors consisted of a single barrel primary and a single barrel secondary on each head, connected by a progressive linkage; in addition, the heads featured a 9.25:1 compression ratio, and the cars received dual exhaust systems. Engines supplied with the automatic transmission after spring 1965 were modified with a camshaft from the 95 Horsepower base engine, and a special crankshaft gear that retarded its timing 4 degrees- the former to increase torque and smooth idle with the Powerglide transmission, the latter to restore some of the peak HP lost at higher engine speeds by the economy contoured camshaft with short timing.

1966 engines were basically carryover from the 1965 models, however Corvairs sold in California (except Turbocharged models) now featured the General Motors Air Injection Reactor System (AIR), and emissions control system consisting of an engine driven air pump that drew filtered air from the air cleaner, and injected a metered amount into the exhaust manifolds via tubing to promote complete oxidation and combustion of exhaust gasses to lower emissions. Specially calibrated carburetors and slight changes to the ignition timing and advance curves were part of the package. The AIR system had an unfortunate effect of sustantially raising exhaust gas, valve and head temperatures, particularly under heavy loads and this was a drawback on the Corvair where engine cooling could not be easily improved to cope with the higher temperatures. Nonetheless, performance and drivability were not noticably effected in most circumstances. In 1968, all Corvair (and other GM) engines got the AIR system for every market.

The 140 HP engine was officially discontinued for ‘67, but became optional in 1967 as COPO 9551-B, not a regular production option. Chevrolet sold 279 of these engines in the 1967 model year, 232 with manual transmissions, and 47 with Powerglide transmissions. Only six were sold with the four carburetor engine and the AIR injection system required by California emissions standards. These figures include 14 Yenko Stingers and 3 Dana Chevrolet variants of the Stinger.

Both the 140 HP engines and the Turbocharged engines had many special quality features not shared with lesser Corvairs- Moly insert top rings, stellite tips and faces on the valves, a Tufftrided (cold gas hardened) crankshaft, and Delco Moraine ‘400′ aluminum engine bearings- the quality of the 140HP Corvair engine for materials is directly comparable to the Rolls Royce V8 of that era, item for item. It was a fabulous bargain for the $79 premium it commanded over the basic 95HP engine. Performance of the 140HP engine was better than you might expect, with a 5200 rpm peak horsepower output, it offered road performance in a Corvair comparable to contemporary Cadillac models of the day.

The turbocharged engine now developed 180 hp (134 kW). Contemporary reviews describe a similarity in power between the turbocharged and four-carburetor engines throughout the low and mid rpm range, with the turbocharged engine being superior only when it was possible to sustain boost continously. The turbocharged engines long suit was highway acceleration, flooring the accelerator at turnpike speeds produced ferocious acceleration in the upper speed ranges as the turbocharger began to boost, reaching manifold pressures approaching 15 PSI. No wastegate was used on the Corvair turbocharged engine, boost was controlled by careful balancing of exhaust restriction, mostly via the muffler, and intake restrictions from the smallish Carter YH carburetor used. Preignition and knock under boost was controlled using a novel ‘pressure retard’ device, essentially a modified vacuum advance device, on the specially curved distributor, as boost pressures built, ignition advance was progressively reduced to preclude detonation.

By:452-engines.com