Hogslayer

fiatfan

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What things did John Gregory invent/improve in the engine? Anything that is used today?
 
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What things did John Gregory invent/improve in the engine? Anything that is used today?
Hogslayer was the first Top Fuel dragbike to use more than 1 gear. Gregory built up a 2-speed Rambler overdrive unit for a gearbox. Also, the clutch was made from an earthmover brake. The Hillborn fuel injection was off a 4-cylinder Offenhauser Indycar engine halved for the two twins. I wouldn't say he "invented" anything, but he fabricated what was needed from other machines because the components didn't exist for motorcycle application at the time. Now Top Fuel dragbikes exist purely for exhibition.

I was camped next to those guys at the Norton Rally at Dick Klamfoth's ranch in Ohio. The part in the film that alludes to the party atmosphere when the team wasn't on the strip is true.
 
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Hogslayer is on Prime and a good watch, it came up in my recommended so did not need to search.
 

maylar

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I finally found it via text search. But voice search on my Roku device didn't work.
 

fiatfan

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Hogslayer was the first Top Fuel dragbike to use more than 1 gear. Gregory built up a 2-speed Rambler overdrive unit for a gearbox. Also, the clutch was made from an earthmover brake. The Hillborn fuel injection was off a 4-cylinder Offenhauser Indycar engine halved for the two twins. I wouldn't say he "invented" anything, but he fabricated what was needed from other machines because the components didn't exist for motorcycle application at the time. Now Top Fuel dragbikes exist purely for exhibition.

I was camped next to those guys at the Norton Rally at Dick Klamfoth's ranch in Ohio. The part in the film that alludes to the party atmosphere when the team wasn't on the strip is true.
In the documentary they say that he did work inside the engine and improved stuff, not specified. I didn´t mean what he did to make the dragbike parts work. Also in the end Gregory claims they did design much of the Fastback and the Roadster, never heard that before.....
 
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Also in the end Gregory claims they did design much of the Fastback and the Roadster, never heard that before.....

:cool:
 
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One thing never mentioned is weight; rather lack of it. The twin-motored bike was said to weigh about the same as a stock Commando and T.C. was the Dani Pedrosa of Top Fuel bike pilots. Had much to do with their holeshots and psyching the guy on the other lane to hammer it too hard and break the tire loose.

I believe Hogslayer was the first dragbike to run an 8" slick on a wide wheel. Their success was from making a great combination of bike and rider. And having access to piles of new parts until the pipeline dried up.
 
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I believe Hogslayer was the first dragbike to run an 8" slick on a wide wheel.
Just another opinion here but I believe much of their success was figuring out how best to use all the traction the larger rear wheel could offer in conjunction with 1.) all the brute torque they were able to deliver from the twin nitro burning Norton big twins, 2.) relatively light rider/bike, and 3.) speed, guts and intuition of the rider.
 
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Hogslayer was the first Top Fuel dragbike to use more than 1 gear. Gregory built up a 2-speed Rambler overdrive unit for a gearbox. Also, the clutch was made from an earthmover brake. The Hillborn fuel injection was off a 4-cylinder Offenhauser Indycar engine halved for the two twins. I wouldn't say he "invented" anything, but he fabricated what was needed from other machines because the components didn't exist for motorcycle application at the time. Now Top Fuel dragbikes exist purely for exhibition.

I was camped next to those guys at the Norton Rally at Dick Klamfoth's ranch in Ohio. The part in the film that alludes to the party atmosphere when the team wasn't on the strip is true.
I was at that rally too.
 

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