Interest in European-style speedway had exploded in the USA after its introduction by Lloyd "Sprouts" Elder during 1931. Several high school sports fields in the Los Angeles area had been turned into speedway tracks during the summer vacation. Local Indian dealer, Albert "Al" Crocker was fascinated with this new sport, so, in partnership with his chief engineer Paul Bigsby, they decided to build their own speedway bike. The initial 1931 prototype was a special Crocker frame into which they installed a regular 45 cubic inch (750cc) sidevalve Indian 101 Scout engine. Satisfied with this frame design, Crocker next turned his attention to a better engine, so for the 1932 campaign several Scout engines were converted into 30.50 cubic inch (500 cc) overhead valve units.
1931 OHV Crocker Indian V-Twin
The first of the Crocker-powered overhead valve singles appeared at Emoryville Speedway in California in November 1933. Cordy Milne rode the machine in twelve races and took nine first places and one second place during the meetings held on November 11th and 14th. His brother Jack had four first places during the same two meetings. Other top riders who used the first Crocker dirt trackers were Miny Waln, Earl Farrand and Snooky Owens, so the marque was well represented.
Unfortunately for Al Crocker, the British J.A.P. powered bikes were beginning to dominate speedway in Europe and were rapidly replacing the Douglas and Rudge machines which had dominated the sport since 1928. The 40hp Crocker proved itself the equal of the Rudge, and was superior to the Harley-Davidson CAC. However, the J.A.P. machines were good for 42-43 hp, so Crocker's new baby needed further development to be competitive. He therefore had two overhead cam motorcycles built during 1934, one of which was ridden a few times by Miny Waln. The 1934 Crocker catalogue stated....
"These machines competed continually at Long Beach, San Diego, Los Angeles, and Santa Ana. In the winter they were sent to Mexico City for a series of eighteen races, where practically every event was won by a Crocker machine. Competition with the imported equipment forced the decision in favour of a newly designed power plant - a type which would have acceleration, the right power output, low cost of maintenance plus a low first cost. A single cylinder type was decided upon."
"These machines competed continually at Long Beach, San Diego, Los Angeles, and Santa Ana. In the winter they were sent to Mexico City for a series of eighteen races, where practically every event was won by a Crocker machine. Competition with the imported equipment forced the decision in favour of a newly designed power plant - a type which would have acceleration, the right power output, low cost of maintenance plus a low first cost. A single cylinder type was decided upon."
Meanwhile, Crocker's attention was turning to a long cherished dream of building the fastest road-going motorcycle in the nation - perhaps the world. Facing stiff competition from the J.A.P. engines, and not being a true factory owner, he abandoned his shop-built speedway bikes at the end of 1934 to launch the far more famous Crocker v-twins which debuted in 1936. During the speedway project, the Crocker machine shop had built between forty and fifty of the pushrod speedway motorcycles.
Key specifications of the 1934 Crocker speedway machine:
Bore: 3 1/4 in (82.55mm)
Stroke: 3 5/8 in (92.085mm)
Displacement: 30.06 cubic inches
Compression Ratio: 14 : 1
Crankpin: 1 1/8 in, drilled for oil
Main Shafts: 1 in, with 7 degree taper
Bearings: roller for mainshafts and crankpin
Valves: 1 3/4 in, set at `close angle' in `shallow domed interior'
Valve Springs: three coil springs per valve
Ignition: gear driven Lucas magneto
Carburetor: two bowl Amal
Power Peak: at 6,000 rpm
Fuel: alcohol
Frame: chrome molybdenum tubing
Gear Ratio: for 1/5 mile track, 8.75 : 1
Weight: 235 pounds
Cost: $385
Information taken from the Book "American Racing Motorcycles" by Jerry Hartfield.
THERE IS SO MUCH GARBAGE OUT THERE REGUARDING THE PRODUCTION OF THE CROCKER MOTORCYCLES. FIRST OFF ONLY 31-32 CROCKER SPEEDWAY MOTORCYCLES WERE PRODUCED. 12 WERE COMPLETE BIKES WITH CROCKER FRAMES. THE OTHERS WERE JUST MOTORS TO BE PUT INTO A FRAME OF YOUR CHOICE. MOST FRAMES SELECTED WERE VICTOR MARTIN FRAMES. SECONDLY ACCORDING TO GENE RHYNE AND HOMER WOOD WHO WERE AT THE FACTORY ONLY 61-TO-64 CROCKER V TWIN MOTORCYCLES WERE PRODUCED. HOMER WOOD PURCHASED THE FIRST CROCKER MOTORCYCLE NUMBER FOUR. I HAVE SPENT MANY HOURS WITH BOTH OF THESE PERSONS TALKING OVER THE CROCKER MOTORCYCLES. ERNIE SKELTON AND CHUCK VERNON ARE OTHERS WHO KNOW THESE MACHINES. ERNIE SKELTON AND HIS FRIEND ELMO LOOPER NEVER WERE CROCKER EMPLOYEES. THANK YOU RANDY WIGGINS.
ReplyDeleteThanks for the information Randy, there's always much to learn.
ReplyDeleteElmo was at the Crocker factory and Al Crocker handed him the Bigsby drawings. Ernie Skelton borrowed the drawings and never returned them. The purpose of the drawings is for manufacture and that is what Ernie Skelton did. Skelton used Harry Suchers bike for patterns, detailed in Harrys article, 'The Fabulous Crocker' AMCA mag 1971. Most bikes have HD rods and pistons simply because no Crocker rods existed. as for Crocker singles, the engine stamps are stuffed by those who built them. eg; 34-62 and 35-30 ,<< great sequence. There is nothing wrong with making replica bikes and engines but to destroy the history of the Crocker company is VANDALISM. Machinists should be recognized for their talent not hidden behind a money game. There were no NOS parts from the factory, Elmo did not buy an inventory. The parts are brand new made by machinists. Randy mentions 12 bikes / motors, theres only 12 months in a year. By the time Homer Wood recieved his bike in July, other owners were already racing at Muroc in April. The HD knucklehead was delivered in march 1936 and raced at Muroc in April. Homer Wood was not the first owner and 14 was not the number Al Crocker mentioned. He said twelve. Skelton and Chuck Vernon said 14, giving a theoretical total of 63, that's 63/14 = 4.5 years. Sam Parriott raced the last big day out, June 1940 , that's 4.5 years from 1936. The Scootabout was released late 1940, ads are in Pop Mechanics, Pop Science Nov Dec Jan Feb. no more V twins
ReplyDeleteFloyd Clymer is the one person who stated there were 31 Speedway bikes and 64 V-twins built. That is quoted in 1961 'Cycle' magazine, his own publication and Al Crocker died in 1961, so no-one could counter any of Floyds claims and no-one has. There is no solid fact with anything Clymer wrote. He was in the book and magazine business, to make money. It was his 'word' that got him into Leavenworth Prison for Fraud. The Crocker factory did not have capacity or the staff to build the number of bikes claimed by Chuck Vernon and Harry Sucher, as well as Floyd Clymer. Clymer's estimation is the only one on record, and that is the one the vintage money machine uses as a foundation, but no-one references it. Harry and Chuck 'built' on it
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