Tuesday, April 14, 2015

A Short History of Harley-Davidson's Early OHV Racers - Episode #33

By: David L. Morrill
@ Deadly Dave's Blog

Updated: July 30, 2015

Early Harley-Davidson Blanked Off OHV Single Cylinder Racer - ca. 1916
Lonnie Isam Jr. Collection
The idea behind this episode comes from a single photograph shared on Facebook by Lonnie Isam Jr. Lonnie's family has a long history of involvement in antique motorcycle restoration.  The photo shows a rider, whose name escapes me, seated an early Harley-Davidson single cylinder overhead valve (OHV) half mile dirt track racer.

The introduction of Harley-Davidson's all conquering eight valve racers of the teens and twenties, is a bit of a mystery. Little is known about the development of these engines, but I have been able to find a few period articles that may shed a little light on the story. In Episode #30, on the birth of Harley's 11-K racer, I detailed Harley-Davidson's late entry in the professional motorcycle racing game.  When they did, they started with a racing engine loosely based on their 1914 production pocket valve single cam V twin. While this engine was quickly competitive, Harley's chief competitors on the track had been racing exotic overhead valve racing engines for years. Harley's Race Engineer, Bill Ottaway, realized he would quickly reach the limit of the pocket valve racer's development, and so he began developing special four overhead valve cylinders. The exact history of when this development started has been lost to time, but it appears it began sometime in 1915.

1915 Harley Davidson Single Cylinder Pocket Valve Racer
R. I. Jones Collection
While Harley-Davidson had a 1915 single cylinder racer, for reasons unknown, Ottaway chose to use the V twin bottom end, as the test bed for his new engine. This was accomplished, by blanking off one cylinder. By removing one cylinder, piston, rod, and rebalancing the crankshaft he created a blanked of 30.5 ci. single. The 30.5 ci class had been created to slow down the 61ci V twins, which were previously used on the half mile dirt tracks popular in the period.

It is pure speculation, but Ottaway may have chosen to develop the new OHV cylinder, on a single cylinder engine, because the single has a straight intake from the carburetor to the cylinder. The V twin uses the same T shaped intake used on the production engines, with the carburetor sticking out to the right or left of the engine.  That style intake creates more turbulence of the incoming gas/air mixture.

Maldwyn Jones made his reputation on the racing circuit riding Flying Merkle racers, but decided to switch to Harley-Davidson for the 1916 racing season.  Bill Ottaway installed one of the new Harley-Davidson blanked off 4 valve race engines into a special lowered Merkle racing frame and fork jones had developed.  Due to his short stature, Jones preferred the Merkle frame's lower seat height, and better fork. Jones would use this bike to win half mile races across the country. Jones also went on to race a Harley-Davidson 8 Valve engine in the same frame and fork combination.

Maldwyn Jones - Harley-Davidson 4 Valve Racer - 1916
R. I. Jones Collection

By April 1916, the OHV single was ready for it's first race test. Several bikes were sent to the half mile races held at Roanoke, Virginia on April 30, 1916. The new single cylinder OHV racers were fast right from the start, with team rider Ray Weishaar wining several races.  He even lapped an "OHV ported" Indian in one of the races.

Motorcycle and Bicycle Illustrated - June 1916
Harley-Davidson wasted no time in advertising the new racer's win, with a two page ad in Motorcycle and Bicycle Illustrated.

Harley-Davidson Ad - Motorcycle and Bicycle Illustrated
July 9, 1916
Now, there was certainly more to Ottaway's plan than just building a single cylinder half mile racer, and there was. He was also, at the same time, developing an eight overhead valve V twin to challenge Indians eight valve racers.

8 Valve Harley Racer - ca. 1916
Lonnie Isam Jr. Collection
For this venture, he also used the 11-K V twin bottom end. New front and rear OHV cylinders were added, and testing began. By June 1916, the new V twin OHV racer was ready to race, and was shipped to held at Detroit, Michigan on June 11, 1916.

 Motorcycle and Bicycle Illustrated - June 1916
Bill Brier won a heat race on the new eight valve racer, but the new racers suffered teething problems in the longer races, and development continued.

On July 4, 1916, the new 8 valve racer proved it's speed by winning the pole for the biggest race of the year, the Dodge City 300. Floyd Clymer, on his first time on board the new 8 valve racer, set the pole time. While Clymer led the race, he eventually slowed with engine problems, Irvin Janke went on to win the race for Harley-Davidson on one of 8 valve racers.
Motorcycle Illustrated - July 6, 1916 

Harley-Davidson Racing Team - 1916 Dodge City 300

The new 8 valve racers showed also their dominance in the 100 Mile Championship Race at Sheepshead Bay, New York. Harley-Davidson took five of the top six spots, proving the new 8 valve racer was more than a match for it's competition.
Harley-Davidson 8 Valve Racer Ad - July 6, 1916
Motorcycle and Bicycle Illustrated 
A new two cam bottom end was developed for for both the V twin racer, and the blanked off single. In the hands of Harley's 'Wrecking Crew" Racing Team riders, both of these bikes went on to become a dominant force in racing for years to come.

1923 Harley-Davidson 2 Cam OHV Racing Engine Patent Drawing
WWAG.COM

1928 Harley-Davidson 2 Cam Racing Engine
R. I. Jones Collection
In 1921, Harley-Davidson ceased involvement in professional racing. They did however continue to provide select riders with race bikes thorough their dealer network.  One of the beneficiaries of this program was Gene Walker of Birmingham, Alabama. Walker, an Indian Factory team member, was one of the top riders in the country.

In mid 1921, Walker was suddenly fired by Indian for refusing to ride in the Dodge City 300. Left without a ride, Walker returned to Birmingham, and went to work for his former Birmingham Indian teammate, Gail Joyce, who was now the Birmingham Harley-Davidson dealer. Walker got his hands on a blanked off two cam Harley-Davidson, and began racing it. How this came about, has been lost to history, but perhaps Harley-Davidson saw a way to poke their former racing rival Indian. Walker would become a dominant force on half mile dirt tracks around the country.

Gene Walker - Harley-Davidson 2 Cam Single - 1923
Don Emde Collection
After dominating the half mile races on the Harley two cam Harley single in 1923, Harley-Davidson issued an ad touting his dominance.

Harley-Davidson Ad - 1923
The Harley-Davidson ad may have been the final humiliation for Indian, as they quickly rehired Walker. Sadly, he died of injuries sustained in a practice crash on the half mile track at East Stroudsburg, Pennsylvania in June 1924.

After Walker's death, Indian threatened to pull out of racing if the displacement was not reduced to slow the bikes on the half mile dirt tracks. The displacement was reduced to 21ci.-350cc. In 1926, Harley introduced a new single cylinder OHV racer, which came to be known as the Peashooter, for the unique popping sound it made. Most of these bike went to Europe, Australia, and New Zealand, but a few stayed here for use on half miles, and cinder tracks.

1927 Harley-Davidson Peashooter Racer
Harley-Davidson CAC Cinder Track Racer

When the Great Depression hit, American motorcycle companies were struggling to survive, and racing activities were curtailed. They would return in the 30s with Class C racing, which outlawed specialty racing machines not based on production models. This was  not the end of the exotic OHV racers.  The technology was used to build alcohol powered hill climb racers.

1930 Harley-Davidson DAH Hill Climber
R. I. Jones Collection

As the years pasted by, few examples of the these early OHV racers have survived, and they are among the rarest of Harley-Davidson's early racers.


Sources:

Bicycling World and Motorcycle Review

Don Emde Collection

Lonnie Isam Jr. Collection

Motorcycle Illustrated.

R. I. Jones Collection