Shaft drive mini sprint
 

Has anyone done this yet successfully other than the Kenyon setup? Hawk makes adapters for the dwarf car guys so I figure this might make this attempt easier to almost bolt one together. Thanks

Re: Shaft drive mini sprint
 

3/4 Midgets have been doing it for years too. Would be easy to do, just wouldn't be legal anywhere.

Bill

Re: Shaft drive mini sprint
 

Pat

The guy at Rod End Supply had a shaft drive 600cc car back in the late 80's. He used an old shaft drive Yamaha 6000cc motor and it looked real neat, great workmanship but it was just a little down in the power department. The problem is the the rear end required a lot of extra power to work and was just not as efficient as the chain drive.

Shaft drives would be legal with the MMSA and down in Florida. The Dwarf cars use an open drive shaft and I know of very few racers that would want that spinning drive shaft between their legs just below their privates.:5:;):5:

Honest Dad himself:6::6:

I was thinking of just using the hawk adapter to be able to bolt up to the front joint at the firewall and use a regular torque tube driveline from the firewall back. I might see about milling a billet spacer to take up the difference in length between the adapter and the front joint. I would guess that space would be 3-4" give or take a little. Maybe the u-joint could be bolted straight to the adapter and the motor plate be "boxed" to accommodate the added driveline length. Gotta love the winter time blues and spare parts staring at you in the shop..... Lol

Re: Shaft drive mini sprint
 

I would think you could machine a blank sprocket bolt it to the u-joint ala Kenyon car. The next problem will be off set for rear end and height of torque ball in relationship to the rear end. Seems they keep raising the sprocket height on the newer motors. You might have to dig a trench around the race track for the oil pan to run in.

Honest Dad himself:6::6:

Maybe......lol I know for a fact that the sprocket height difference between a oil cooled gsxr1100 and a r1 is almost 3". Seeing that new zx10r and thinking how could you drive the car with the air cleaner almost being in the way. That engine sure is tall....

What would be the advantage?

Re: Shaft drive mini sprint
 

Bd

The advantage?

1. You would be different from the rest of the pack.

2. You wouldn't have to worry about that old chain slinging chain lube everyplace.

3. Down in Florida you wouldn't have to worry about premature chain wear due to sand.

4. changing gears would be super quick, instead of 30 minutes you could do in in 3.

5. You would look just like a real Midget race car.

DISADVANTAGES:::

1. You would add about 40 to 50 pounds to your race car.

2. You would run into problems adapting it to your motor.

3. There would be about a $700.00 premium for parts.

4. You couldn't brag about being chain drive.

5. You take a 20% hit in your rear wheel horsepower because the M/E loss between using a hypoid gear as opposed to chain and sprocket.

Honest Dad himself:6::6:

Re: Shaft drive mini sprint
 

Pat,
What's the offset between the crank & countershaft on your R1? Montpelier and MMSA still want you to keep it under 6" with the drive shaft on the centerline.
Dad,
Regarding the $700 premium, wouldn't you eventually eat that up replacing chain and sprockets?
What's M/E loss? we talkin' drag/friction here?

Re: Shaft drive mini sprint
 

Jim

Yep that chain is expensive.

The efficiency of a Hypoid gear with a very low mounted pinion aka rear end is down around 90 to 95% multiply that by the 95 to 98% efficiency for the quick change gears and you get something like a 20% loss of efficiency. Them rear ends get hot and that heat (friction) is due to sliding of the teeth in the Hypoid type gears. This eats up horse power. That is why they make special oils for Hypoid gears because regular oils just aren't strong enough to work with them.

Problem:: if you placed the motor fore and aft in the center of the chassis the drive shaft is already offset to the right several inches. Place it 6" offset to the left and the drive shaft is probably going to be inline with the brake pedal. Then you got to figure out how to raise the drive line or drop the engine enough to get the drive shaft in-line. TQ's fix this problem by chopping off the transmission. That worked OK with the low rpm of the 750 Honda but to try to gear for 13,000 RPM's + with an 82" tire with only the rear end gears is not possible right now. Boy that is going to be a strange looking quick change.

I could see probably a jack shaft with timing belt being used for both motor placement and gear ratio. When somebody finally does this I'm going to put two of these things in a race car and go race full midgets Ala dual engine go Karts. They weren't a whole lot faster but boy did they give you a kick in the butt when you got down on them.;) Wonder if they would allow Dual Right Rears?

Honest Dad himself:6::6: