50th Anniversary Of Jet Fire Orange

1970 Harley-Davidson XR-750

I’m talking about the Harley-Davidson XR-750, which last month marked the 50th Anniversary since it’s debut.

From 1953 to 1969,  Harley-Davidson manufactured the KR750, the backbone of American dirt track racing.

The motorcycle engine was an air cooled, side valve 4-stroke 45° V-twin (flathead), 45.125 cu in (739.47 cc) displacement built for racing.  Unique for Harley’s at that time, the KR model shifted on the right, like a British bike, which worked great for dirt track.  It wasn’t until 1975, when DOT specified that all motorcycles sold in the U.S. had to have a standardized, left-side gear shift.

Harley-Davidson Flat Track Racing

Prior to 1969, the American Motorcyclist Association (AMA) rules for the Grand National Championship were structured to favor “sidevalvers” (side-valve engines) rather than overhead-valve (OHV) engines.  The intent was to deliberately favor American made bikes such as those from Harley-Davidson with their side-valve engines, and disadvantage the competition which was mainly from British manufactures i.e., Triumph, BSA, and Norton. The AMA rules allowed side-valve engines of up to 750cc capacity but OHV engines were limited to 500cc. The 50% engine size advantage stacked the odd in the favor of the side-valve bikes.

As you might imagine, the British manufactures complained…about everything—the rules, the manufactures, the officials, the drivers, the races, and the racing itself.

Harley-Davidson XR-750

As a result, in 1969, in prep for the 1970 race season, the AMA approved that all professional Amateur & Expert dirt track and speedway engines could be 750cc, regardless of configuration or valve style. This rule change eliminated the 250cc penalty for OHV engines that had existed since 1933.  Many British manufacturers begin designing and developing OHV 750cc engines for competition. To be approved by the AMA (for Class C competition), a motorcycle must be a standard catalogued production model and at least 200 units of the same model with identical engines and transmissions and must be available for inspection and/or purchase within the United States.

XR-750 Engine – Ported and Polished Heads

Unhappy with the decision, but with a desire to continue the racing legacy, Harley-Davidson set out to create a new overhead-valve racing motorcycle.  The Milwaukee motor company leveraged their OHV V-twin racing engine based on the Sportster XLR.  However, it’s engine had a displacement of 900cc (55 cu. in.) and would need to have its capacity reduced to 750cc. Harley-Davidson engineers accomplished this by decreasing the engine’s stroke from 3.81″ to 2.983″ and increased the bore from 3.0″ to 3.2″ bringing the engine in just under the 750cc maximum.

The AMA approved the Harley-Davidson “XR”, a 750cc V-twin overhead valve engine, for Class C competition on Feburary 27, 1970. It had been tentatively approved in late-1969 as the “750 Sportster”, but the motor company lacked having 200 units available for inspection at the time. The motorcycle is dubbed the “iron XR“, or “Iron Head,” due to its steel cylinders and heads.

Even Knievel

For the 1972 race season, there were a number of changes.  A vote was taken on November 18, 1971, and the AMA Competition Congress voted to allow qualified women to compete in all forms of AMA Racing.

The Water-Cooling was approved, as long as it is an integral part of a production motorcycle.  Titanium frames were outlawed from all AMA competition. The AMA approved the Harley-Davidson XR-750, an updated version of the XR, for Class C competition on April 12, 1972. The updated engine used aluminum cylinders and heads to address the overheating issues that plagued the XR model. However, due to delays in getting all 200 units completed, it wasn’t approved in time for the Daytona 200, but debuts at the Colorado Springs national on April 30, 1972.

Speaking of aluminum heads, they were made, then shipped to Jerry Branch of Branch Flowmetrics in Long Beach, California to be ported and assembled. The new cylinder head design included larger valves. The cylinder heads were then shipped back to Harley-Davidson’s factory in Milwaukee for fitting to the new engines. This V-twin engine was not quite of the same dimensions as the Iron Head. The bore was increased to 3.1” and the stroke reduced to 3”. Carburetors were 36mm Mikuni, one for each cylinder. The exhaust systems were mounted high on the left side of the motorcycle well away from the carburetors.  Power was 82hp at 7,700rpm giving the bike a top speed of around 115mph.

Harley-Davidson Flat Track Racing Team

Branch wrote engineering books on his engine air flow work and eventually sold Branch Flowmetrics to Mikuni in the late 1990s.  Branch was the only independent company to ever supply Harley-Davidson ported and polished heads!

In 1972, Harley-Davidson was the first-ever “Grand National Manufacturer’s Championship“, which compiles the highest finish of each brand at every Grand National Championship event.  Between 1972 and 2008, the XR-750 won 28 of 37 AMA Grand National Championships. The XR-750 racked up more wins than any other motorcycle in AMA racing history and earned the description of being the “most successful race bike of all time.”  In addition, the XR-750 became a cultural icon with legendary stuntman Evel Knievel at the handlebars. Evel Knievel began jumping an XR-750 at the height of his career from 1970 to 1976.

Harley-Davidson created one of the greatest bikes in the history of American motorcycling.

For 2020, the Harley-Davidson Factory Flat Track team will use the updated Harley-Davidson® XG750R flat tracker, powered by the liquid-cooled, fuel-injected and race-tuned 750cc Harley-Davidson® Revolution X™ V-Twin designed for the Street 750 motorcycle.

Full details on the Flat Track team can be found HERE.  Flat Track racing news is HERE.

Photos courtesy of Harley-Davidson

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Harley-Davidson And The “The King of Good Times”

I’m talking about Kingfisher.

Beer was introduced into India by the British, who eventually set up a brewery that produced Asia’s first beer — a pale ale called Lion. However, these days, lager is the only type of beer you’ll find available in India and “The King of Good Times” is Kingfisher.

It’s India’s most recognized and widely available beer. Its name has been associated with sports, fashion, and even an airline.

And sooner than anyone would have thought… in Bawal, India a Harley-Davidson assembly line worker will be having a Kingfisher and relaxing with co-workers.

But, I’ve gotten ahead of myself…  let’s jump into the the way back machine and set the dial for — 2009.

“The fact is we must focus both our effort and our investment on the Harley-Davidson brand, as we believe this provides an optimal path to sustained, meaningful long-term growth,” said CEO Keith Wandell at the October 15, 2009 announcement to discontinue production of Buell motorcycles.  On October 30, 2009 the last Buell (Lightning XB12Scg) rolled off the company’s East Troy, Wisconsin. assembly line.  It was the last of the 136,923 motorcycles built in the company’s 26 years of operation.

Harley-Davidson Street 750

It was a combination of factors in making the decision, but essentially the global recession forced a reckoning and Harley-Davidson decided to refocus on its tent pole products or what I’d call doubling down on its core lineup of heavyweight bikes.  As a result, the motor company abandoned entry level motorcycles (Buell Blast), exited the sport bike (Buell and sold MV) and thumb their noses at the adventure market (Buell Ulysses).   In the process the motor company made a lot of motorcycle enthusiasts upset about what looked like a myopic approach of only looking at spreadsheets versus doing a bit more market research and addressing a need.

Jump ahead 4-years and witness the financial rebound of the company and the launch this week of the new Harley-Davidson Street 750 and Street 500 motorcycles.  Could it be a Buell Blast ReDeux?  The smaller 500cc motorcycle basically fills a void left when they discontinued the Buell motorcycle line which included the 492cc Buell Blast.  More important in this announcement is the fact that the motorcycles will be made both in the U.S. and Bawal, India, marking the first time the company will manufacture a complete motorcycle at an overseas facility.  I’ll repeat that… the first time the company will manufacture a complete motorcycle outside the U.S.!

Harley-Davidson Street 750 (Side View)

The manufacturing news in of itself will be fodder for many future blog posts, but sticking to the motorcycle announcement, the new ‘Street’ bikes are the first Harley-Davidson motorcycles to be designed from scratch since the V-Rod 13 years ago.

It makes this Road Glide owner wonder if that’s an indicator of where all the engineers were redirected in lieu of updating the ‘Glide’ with the all new Project RUSHMORE features that were incorporated into the new 2014 touring models?

The fact is the company has aggressively expanded its marketing efforts because realistically, there is no replacing white Baby Boomer men. And this means they have to attract younger men, non-Caucasian men, women, and do that from countries as disparate as India, Italy, Brazil and the U.S. with much more success.  By turning inwards, relying on a single-brand tradition and nationalism over the last 4-years and divesting itself of brands that were dimming the lights on a brighter future–the motor company can and now has expanded into other segments.

At the Street 750/500 announcement the Harley-Davidson, CEO Keith Wandell said, “The younger riders don’t want their dad’s chromed-out Harley,” “They want the Dark Custom, sinister look, the ability to rebel.”

Sounds like a bit of marketing spin, but with more than half of its dealerships outside the U.S., Harley-Davidson has really put a lot of investment behind a push to expand and broaden its customer base including new motorcycle buyers–worldwide.

Photo’s courtesy of H-D and Kingfisher.  Note: Kingfisher, “The King of Good Times”, is India’s most recognized and widely available beer. Its name has been associated with sports, fashion, and even an airline.

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