Let's delve into the real history behind the Harley-Davidson XR-750. By examining the history of the racing industry and the previous bikes that were used in competition, we can see how the past influenced the creation of this influential bike - a bike that would later go on to be ridden by one of the most famous stuntmen, Evel Knievel. After you read up on some facts about this famous stuntman and some photos of daredevils and their motorcycle stunts, you will appreciate the dangerous and risky career led by Evel.

History Of The XR 750

via New Atlas

Before 1969, the American Motorcyclist Association rules were created and put in place to favor side-valve engines instead of overhead-valve engines. The result of this rule was to favor bikes from American-made companies, such as the infamous Harley-Davidson. On the flip side, this rule proved to be a disadvantage to the British companies, like Triumph and Norton.

After a while of abiding by the rules, the Brits were put off by the restrictions, and leveled with the AMA to create a fair playing field. The rule was enacted to allow both side-valve and overhead-valve engines shortly after 1969, allowing both types to be used in the AMA Grand National Championship.

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Iron Head 1970-71

via Mecum Auctions

To create a new overhead-valve motorcycle, Harley-Davidson already had a model they could use for innovative creation. They based their new motorcycle on the Sportster XLR, although they would need to reduce the capacity to 750c. To do this, Harley decreased the engine's stroke to 2.98".

The engine that was based on the Sportster XLR featured a four-camshaft design, providing individual camshafts to operate each valve. This method has the advantage of allowing each push-rod to be at an optimal angle.

The XR-750 Harley-Davidson flat track bikes were used during the 1970-71 racing season. They were pretty successful during specific conditions, but faltered when the conditions were too hot.

Bike Specs

The V-twin engine used in the XR-750 used a four-speed gearbox, and was installed into a unique frame meant for track racing. The XR-750 was so well balanced that it became a favored stunt bike... and broke records.

The Harley-Davidson crew reduced the frame tubing to just 1" diameter, used a 2.5 US gallon fiberglass unit for the fuel tank, and utilized 19x4" wheels with aluminum rims. The weight of the bike was just 295 pounds.

Alloy Head 1972-85

via Silodrome

With the XR-750 showing success in certain conditions, the engineers knew that they needed to improve their bike and have it run cooler to continue a successful career. New alloy heads were added, with larger cylinder valves for cooling.

The V-twin engine bore was increased, and the stroke was reduced. The exhaust systems were placed on the left side of the bike, farther away from the carburetors. The top speed of the bike was around 115 miles per hour.

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A Stunt Bike

via History

Although this bike was created to be a track racing bike, the most famous use of this bike was for a legendary motorcycle jump. Evel Knievel adopted this model back in 1970 when it was a very new model. He used this bike from virtually its inception all the way until he retired in 1976.

Using this bike, Evel recorded a 129-foot-jump over a whopping 19 cars in 1971. At this point and time, the XR was still using an ironhead engine. He also completed a 133-foot-jump over 14 buses in 1975.

In addition to Evel's successful stunt career, this bike has also been used in other worthy feats. Bubba Blackwell used an XR-750 to jump 157-feet over 15 buses in 1999. Years later in 2015, Doug Danger jumped with the same Harley used by Evel in 1972. He jumped over 22 cars at the Sturgis Rally, beating the former record by just one car.

The Overall Truth

Although the XR-750 bike was not meant as a stunt bike, that's just what it became. This bike was manufactured basically out of pressure from the racing organization and USA's foreign competitors, they created a bike they didn't want to, and it ended up becoming an infamous bike in the motorcycle world.

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