See the U.S.A. On Your Chevrolet...
TAKE one Chevrolet Corvette engine, bored out to 305 cubic inches and putting out an equal amount of horsepower, a custom made frame sporting a 1947 Harley-Davidson fork assembly using a 21-inch Norton wheel, a 14-inch rear wheel and brake unit borrowed from an airplane, mounting a 9.50 x 14 Inglewood slick, and what do you have; one of the largest motorcycles you ever saw, that will do a standing quarter-mile in 10.46 seconds and turn 141.56 mph in the process.
This pretty well capsules what Peter Conradson and Rowland Gray created when they started building their drag bike back in Detroit. The boys are located in Long Beach, California now and the bike is run here under the sponsorship of Paul Burkhardt of Burkhardt Inc., formerly known as California Cycle Specialties. Today Paul is not only the sponsor but he shares in the tuning chores and performed the myriad machining and engineering details necessary to finish the bike.
Though not the fastest drag bike around (Clem Johnson’s beautiful custom Vincent holds the record at over 150 mph but the bike runs on fuel whereas the Chevy-powered monster bums pump gasoline), it holds the record in its class. Small, wiry and possessing the necessary strength and courage is Bob Ryan, official rider who was aboard during their record run. The builders feel that they are still in the teething stages of development on the machine and they expect to continue to add to the laurels already collected.
The huge Chevrolet engine sits sideways in the 68" wheelbase cycle and drives the gigantic rear wheel through a double disc Velva-Touch truck clutch and an 1800 pound Ford pressure plate via #60 roller chain. The clutch turns at 2/3 engine speed; no gearbox is used. Gear ratios, for those who might also be so madly inclined are: 24 tooth sprocket on the engine, 32 on the clutch, 19 on the counter shaft and 54 teeth on the rear sprocket; overall ratio is 4:11.
Additional details on the engine include: four Fish carburetors, Pounden magneto ignition and, though naturally a water cooled engine, no radiator is used. The IV2 gallon header tank is topped up before a run and the temperature range averages 140 degrees at the start, to only 180 degrees at the finish. A Triumph tachometer drive operates off the front (or right hand side, if you will), of the engine.
The special frame is fabricated of 1V4" mild steel tubing, and total weight of the cycle is a staggering 700 pounds! A vast figure for a motorcycle, but not so heavy for an automobile. The boys say that weight is their number one enemy, and though they have been building for 3Vi years, they are just now getting serious!
A rather spartan instrument panel informs the rider of rpm, water temperature and oil pressure. The interesting airplane wheel used in the rear is an alloy affair, 14" in diameter, with a two-shoe internal expanding brake that is exposed to the air for rapid cooling. A Girling sports car brake master cylinder is used.
We haven’t decided whether it is a motorcycle or a two-wheeled car yet, but there is no question that it takes a heck of a lot of motorcycle to stand up to it.
Interesting goings on at Burkhardt Inc. do not end with this machine. At present they are deep in the throes of building a special 108 cubic inch HarleyDavidson (more or less) engine for Mr. Doug Gall in Minneapolis, Minn. Burkhardt is using only the cases and heads of the original Harley and is fabricating rods, flywheels, pistons, cylinders, crankpin, and a great deal more. Ultimately it will rest resplendently in a Harley frame and perform for the people at the drags in the Minneapolis area. We are certain to hear more of this bike as time goes by.
ALL GO!
See the U.S.A. on your Chevrolet. . .
