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Chuckthebeatertruck 20th July 2021 19:37


Originally Posted by perfesser (Post 5906103)
my understanding was the record run was on gas. a closer reading of the document provided does reference a fuel setup.

The confusion is because there were three record attempts at the same time with overlapping people in 1969 and 1970.

Warner Riley did set gas records on an 89" bike and later on a 96" bike -- claiming 15 or 16 records between 1969 and 1975.

Leo Payne was well known for being a fuel (nitromethane) lover. He was the first person to take a non-streamliner over 200mph. He did it on a heavily modified, 75 inch motor based off a 1957 sporty.

When I see folks on here and other motorcycle sites describe themselves as "builders" because they bought some parts off the shelf and did some welding, it's pretty clear they don't walk in the same camp as folks like Leo Payne. To achieve his goal -- Leo "built" a carb. Doc Dytch made cylinders. Tom Sifton made cams. Warner Riley knew how to build a bike the factory never thought of.

Those folks were builders and the pioneers.

Welding on a hardtail and stupid ass jockey shifter does not a builder make.

Pioneer your own fuel carb, set a record, and then mass produce it . . . and you've earned the right to call yourself a "builder."

perfesser 20th July 2021 20:03

thanks for the followup. understanding that all alcohol fuels have lower btu content than gasoline thus requiring larger jets, and that the only way to make more power is to get huge amounts of mixture into the combustion chamber as possible, i should've realized this was a fuel carb. got busy trying to wrap my head around how a 1200 would even run with an 8 sizes larger 230 main jet.

brucstoudt 20th July 2021 23:00

did you find anything else interesting at Wauseon?

Ferrous Head 21st July 2021 00:19


Pioneer your own fuel carb, set a record, and then mass produce it . . . and you've earned the right to call yourself a "builder."
We all stand on the shoulders of giants.

The frame I race on was designed by me, hand bent and welded in a mate's garage. That includes the leading link front forks.

But the basics were there long before I came along. And I had other world class frame builders to talk to while doing it. Even then, my first design wasn't perfect.

The vast majority of people modifying bikes don't do it for a living. They have to support themselves and their families along the way. And most simply don't have the metal resources and the acquired skills required to do these things.

Several times in my life I thought I would like too build a bike. Really build one. Cat the cases, barrels, everything. Do the machining. Buy a frame jig. I bought a lathe and mill to get started. Bought the things I needed to do alloy casting. And set about designing a very simple 500 single. This exercise always morphs into something much bigger. Because it's not that much more to do a 1000 cc V-Twin. And very soon I realise I'm just designing a Ducati 900 all over again and I stop.

Why reinvent the wheel.

Ferrous Head 21st July 2021 00:30

Oh. Carburetors.

I'm with NeedSpeed on this. I think any carb can be made to work as long as it's sized commensurately. eg the 1 7/8ths L is a little big for a 900 Sportster. (Although it will sort of work)

Some members may be familiar wit a surface vaporizer. This consists of a flat plate that gasoline drips on to and is located just below a tube that leads to the combustion chamber. (How this goes on a windy day is anybody's guess.)

believe it or not this is what they used before B&B or somebody came up with a "proper" carburetor. One based on the Bernoulli effect.

The idea may seem laughable but these surface vaporizers are still used by some manufacturers. The last time I looked Victa Lawnmowers were still using them.
They are much unproved of course, now being rolled into a cylinder and encased inside another cylinder. But that is what they are, surface vaporizers. Cheaper to make than a carburetor it appears.

And they do the job. I'm not saying they do the best job possible, but they do the job required of them.

Ferrous Head 21st July 2021 01:24

I have boxes of carbs. all kinds.

S&S, Tillotsons, Linkerts, Kehins, Chinese copies of S&S's, not to mention spares and jets etc.

I am planning on running this MGAL on the big bore stroker when it's finished but will be starting it for the first time on a Chinese S&S. Simply because it's a no brainer to make that work.

If I had a fuel version I would have a go at runing this engine on Methanol.
(Just for the hell of it, never going to rce it.)

Mostly I just use a Super B. Easy to install/use. Adequate performance for most engines. More than enough carb for a 900.

By the same token, here's everything I know about EFI.

(That's crickets you can hear)

11B40 21st July 2021 02:52

Funny to say this but if you happen to have a "Good" Tillotson, they are pretty nice carbs. I ran one on the '66 900 before I got the GAL. It had an adjustable main jet which was handy. You can ride down the freeway and change the setting and get instant feed back. Mine started fine and never vapor locked. Got kind of shitty gas mileage probably because of the accelerator pump. Not bad for a chain saw carb. The GAL on the 900 was a serious improvement. I had PB cams and XLR valve heads. The GAL was instantly a much better runner, no flat spots, much better gas mileage, about 10 mph faster in the 1/4 mile at Fremont and Sears Point. The best part was when I went to 77" I just changed main jets and used the same emulsion tube. Needed a wider manifold. GAL GBL both great carbs.

ryder rick 21st July 2021 07:41

THAT is not the best carb for my Ironhead! :)

11B40 21st July 2021 17:48

Right Rick, that was/is the most hated carb ever put on a Sportster. The 1 in a 100 that works well is hard to find. I had zero problems with mine, it worked well and started fine. Funny thing, the guys who had the most trouble with them were the guys who were always screwing around with them, sticking toothpicks into holes to relieve vapor lock and stuff. The GAL was a monumental improvement. If a person could find a good DC, they are probably the best stock carb around. The GAL is just a big DC in a lot of ways. The DC is a very cool looking unit as well. I have no experience with the Bendix and Japanese carbs as they came after I quit.

kitabel 21st July 2021 19:19

He "built" a carburetor... out of an S&S carburetor. Didn't see his name on the casting.

It's called "modifying".

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