The evolution of Harley Davidson's engines

A mith. I will start my first post with this affirmation. Never before a motorcycle's brand have conquered the hearts of so many riders how the Harley have made. There is a legion of passionate enthusiasts around the world that follow all things related with this symbol. I'll not introduce anymore nothing about Harley, because I think that you know many things about her. An manner that I have found to start my blog is showing the changes and the evolution of Harley's engines. This piece of art has made a long course through the roads of all world. So let´s go...

The first engine:

When the friends Arthur Davidson and Willian S. Harley has decided to put a little engine in a bike chassis, they were creating a classic on two wheels. Was born the first Harley-Davidson in a small place with 8m².

The first one

1909-1929 Intake Over Exhaust (IOE): Harley's early single-cylinder motors had overhead intake valves that were opened by vacuum rather than mechanical cam action. The first V-twin introduced in 1909 likewise had vacuum-operated intake valves-which didn't work particularly well. When it was re-introduced in 1911, the V-twin had normal cam-actuated intake valves. Exhaust valves were mounted in the block (side valve) in all cases. Early V-twins displaced 50 cubic inches; a 61-cubic-inch version was added in 1912.

First V-Twin in production

Second generation: Flathead engines

This engines was built between (1929-1974) and had no valves in the head, instead, they were located along the engine and opened upwards into a chamber next to the combustion chamber, the advantage of the head-plan was simplicity - no rods or rocker arms and a single piece with a hole blown into the spark, a typical Flathead engine had a displacement of 742 cm3 and produced about 22 hp.

Flathead

Third generation: Knucklehead engines

Manufactured between 1936 and 1947, the Knucklehead came from variations of 990 cm3 and 1200 cm3, capable of producing 40 bhp and 45bhp respectively.

knucklehead

Fourth generation: Panhead engines

Manufactured between 1948 and 1965, the Panhead came in variations of 990 cm³ and 1200 cm³, capable of producing 50 bhp and 55 respectively, the large differences between the Knuckehead and Panhead include aluminum heads and the internal oil lines, as opposed to Knucklehead of the external lines.

Panhead

Fifth generation: Shovelhead engines

Some improvements in this engine but not significative, the Shovelhead was manufactured between 1966 and 1985; the Shovelheads had 1200 cm³ and produced 60 hp.

Shovelhead

Sixth generation: Evolution engines

Manufactured between 1984 and 1999. The displacement of 1,340 cm³ and the engine produces 70 hp, while the Evolution of 1,340 cm³ is no longer produced, the line of motorcycles model Sportster uses the Evolution engines with displacements of 883 cm³ and 1200 cm³ manufactured since 1986.

Evolution

Seventh generation: Twin Cam 88 engines

Manufactured since 1999, the Twin Cam got its name from having two commands in the block to actuate the valves, with 1 450 cm3, is the engine of the Harley motorcycle more produced and produces 80 horsepower, the engine remains air-cooled and has valves in the head driven by rods and rockers; version of the 88B engine, which came out in 2000, brings two shafts counter-rotating balancing to reduce vibration.

Twin Cam 88

Eighth generation: Revolution engines

Began to be manufactured in 2001, the Revolution engine is currently used only in a production model of the Harley - the VSRC. While all the engines previously mentioned are virtually the same and represent progressive improvements, the Revolution engine is different, it is water-cooled rather than air, and the angle of his "V" is 60 ° instead of 45 °, it has two camshaft in each head instead of two on the block and incorporates fuel injection, it is smaller, only 1130 cm3; engine's stroke is shorter, allowing it to turn at 9,000 rpm and produces 115 hp.

Revolution