Mike Madden’s 1940 Big Tank Crocker motorcycle at the 2005 Legend of the
Motorcycle show in Half Moon Bay, Calif., where it garnered Best of Show.
In the period before World War I, at least 100 different American motorcycle brands appeared on the market. In the 1920s, two or three intrepid U.S. manufacturers came out with new bikes. In the 1930s, the only American to commence the manufacture of motorcycles was Al Crocker with the legendary Crocker motorcycles.
Crocker worked for the Indian Motocycle Company in the late 1910s, not long after graduating from engineering school. By 1928, he was the Southern California Indian distributor, but what he really wanted was to go out on his own.             Â
Crocker bought a machine shop, where he made aftermarket parts such as a steering dampener for Indian Chiefs as a sideline. He would have probably continued his main business selling Indians, had it not been for the speedway craze, a type of short-track racing on a cinder course.
In 1931, racers from Australia gave speedway exhibitions in Southern California, touching off a brief speedway fad across the U.S. Seeing an opportunity, Crocker designed and manufactured special speedway competition cylinders and heads for Indian Scouts. About this time, he met up with Paul A. Bigsby, a patternmaker by trade, who shared Crocker’s love of fast motorcycles. Bigsby soon became an integral part of the Crocker motorcycle operation.
Crocker decided a single would be better for speedway racing than the modified Indian twin, and built approximately 31 hemi-head, overhead-valve, 500cc single-cylinder racers between 1932 and 1935. This was at odds with his working for Indian, so Crocker sold his Indian franchise to Floyd Clymer around 1935. Crocker singles were campaigned by some of the top riders of the era, and were very successful until English-built J.A.P. race bikes appeared in 1935.
Crocker put the speedway aside, and encouraged by Bigsby, started work on a sporty, overhead-valve, V-twin bike. By 1936, testing was so successful that Crocker installed Bigsby as chief engineer and began producing the Crocker V-twin. He immediately ran into a piece of bad luck: Harley-Davidson finished development of its own overhead valve sport bike soon after the Crocker twin hit the market. Making matters worse, the Harley also featured a constant-mesh transmission, but with four gears, a step up from Crocker’s three.
Crocker motorcycles had a performance edge, however, especially in the early days when the Knucklehead’s bugs were still being worked out. But a Crocker cost $495, when a top-of-the-line EL Harley sold for just $380. However, every Crocker was basically custom built, and few are alike. For example, there are at least four different versions of the original hemi-head, and five different parallel-valve top ends.
 The crankcases were heavy aluminum alloy and the cast iron cylinders were so thick that although Crockers were designed as a 61ci (1,000cc) with a bore of 3.25in, overbores to 3.625in without distorting the cylinder are possible. A Crocker motorcycle can be built up to 90ci (1,476cc) through a combination of boring and stroking.
The first Crocker motorcycles were hemi-heads with cylinders similar to the speedway machines. Although fast, they leaked oil and developed cracks in the heads after hard use. In 1937, Crocker introduced redesigned heads with the valves positioned vertically over the piston.
The new heads didn’t throw oil or crack as easily, and produced about as much power as the earlier hemis: 53hp to 55hp at 3,600rpm, depending on whose bike was tested on which dyno. Here’s a video tribute to Crocker motorcycles:
Unfortunately, America’s entry into World War II made it impossible for Crocker to get raw material for his bikes, and he was forced to turn his machine shop over to war production. This was probably a blessing in disguise, since it cost so much to build each bike that he made little to no profit. It’s rumored he lost money on every bike he sold. When the war ended, he decided not to return to the motorcycle industry.
Crockers were not mass produced, and estimates of how many were made range from 61 to 104 road machines, with many experts agreeing on 75 complete motorcycles manufactured. And had it not been for Elmo Looper and Ernie Skelton, there would probably be few left. Elmo bought out Crocker’s remaining stock a few years after the end of World War II, while Ernie enjoyed riding his Crocker so much he regularly took it to meets to let other people ride it: One ride was enough to spark Crocker fever in many folks, and the remaining Crockers in Looper’s care were rescued and restored. The brand itself was reincarnated in 2006 as the new Crocker Motorcycle Company. Â
Special thanks to Chuck Vernon and the late Ernie Skelton, who is sorely missed by all.