The Search for Fuel Economy

Pages from a Designers' Notebook

Freedom Machine
The goal: 100 mpg at 70 mph, into a 30 mph headwind, with four bags of groceries.
Chap. 37: The 2010 Vetter Challenge
So, what have we learned here?

The winner was to be determined by dollars and cents. Surprise!

250 cc Hickey HyperRocket
The winner: 1.535 gallons $4.45
Craig Comments:

What a story this is. The HyperRocket was made by John Hickey, an engineer at Ford who claimed it would do 105 mpg at 65 mph. It was purchased by Steve in California, arriving in SLO the day before the Challenge. "Could he run it?" the new owner asked. Of course!

What an opportunity. Many of you are constructing machines based around the Ninja because of its extra-ordinary power and famed fuel economy. Stuffing such a powerplant into a tiny, streamlined shape would be serious competition, indeed! It reflects clever thinking and craftsmanship. I suspected - and so did the others - that the HyperRocket was going to win.

Pros: No helmet is reguired. Pilot sits in a very comfortable position, strapped in. It will carry a second person - or 4 bags of groceries. Steve said it was not affected by the winds. Thinner motorcycle tires are said to improve the mileage but Hickey has certainly got the BIG PARTS right. 81 mpg is fantastic performance in the Vetter Conditions.

Cons: Wide turning radius... just plain wide, actually. No lane splitting with this machine. No reverse meant that Steve (and those around him) did a lot of pushing. He kept his Snap Vents closed to minimise drag so it was hot inside the bubble. The HyperRocket is difficult to get in and out of. Your author could not do it without help. Son, Zak, gave up. He was just too big. Since so much has already been done, I suspect that not much more is possible in the way of fuel economy improvements. It is probably the end of the road for quantum gains for the Hickey HyperRocket.

*In debriefing, Steve mentioned that we must have over-filled his tank because fuel was splashing out so much that the chase machine, Alan's CRF noticed it too. The HyperRocket, in reality, probably got even better mileage than this Vetter Challenge showed.

Later, I interviewed designer/builder, John Hickey, complimenting him on beating the West Coast's finest. John mentioned that he could give Steve tips on doing even better in the future. In any case, John Hickey has set the mark to beat for a future challenge.

This is racing for the right reasons.

Hayes Diesel
Second: 1.396 gallon $4.61*

Craig's comments:

Motorcycle history was made today with the first public demonstration of the Hayes Diesel. The Diesel performed as advertised. Fred Hayes, piloting his own creation, consumed the least fuel... ( B20 Bio-Diesel, by the way ).

Fred consumed the least fuel. But, the winner was supposed to be the one that consumed the least fuel in dollars and cents which means the Hayes Diesel took second.

Hayes' results amazed me. His already tall motorcycle is boring a big hole in the air. He is not streamlined at all. What would be possible if he was really streamlined? We may be able to find out soon as the company is actually going through the certification process to be legal to sell not just in the US but around the world.

If I could, I would start over with a Hayes Diesel.

Pros: Fantastic fuel economy with no streamlining at all. It starts, rides and sounds like a regular motorcycle. Since nothing has been done to improve streamlining and rider comfort, this is the beginning of the road for the evolution of this bike.

Cons: It is not yet available. The standard (KLR) motorcycle configuration may appeal to many, but it is large and difficult to streamline. I have a KLR gas motorcycle, which is identical in size. I have a hard time throwing my leg over it, making it not particurlarly comfortable to use. It is not able to carry 4 bags of groceries either.

*Unfortunately, the gas station we filled up at in Salinas had the most expensive Diesel in the area ( $3.30/ gal.) and the cheapest gas ($2.90/gal). The next station had $3.21 Diesel, but we had already filled. Fred paid $.13 more than he should have which, to be fair, means it should have cost Fred $4.48. Still, this was 3 cents more than the winning HyperRocket.

250 cc Streamlined Helix Scooter
Third: 80.1 mpg*

(but did not finish)

Craig comments:

I led the way, accelerating aggressively, running wide open up the Cuesta ( the big hill outside SLO) and into the head winds toward Salinas, indicating 67 mph when it was posted 65 mph and 73 mph when it was posted 70. To their credit, the other bikes stayed right with me. Alas, setting the pace and setting the standard for the Vetter Conditions has proved to be too much for my poor little Honda. It was not made for the speeds the streamlining has allowed it to do. It finally broke, 89 miles into the trip.

Filling with Graduated cylinder
The way it should look
Cover split; shaft broke in two
We refilled by graduated cylinder to calculate the mileage 89 miles into the trip. After disassembling the Helix, I found that the welding on special gears caused the shaft to crack in two. In addition, the aluminum cover was cracked. The Streamlined Last Vetter Fairing Helix will have its original gearing re-installed and be retired from competition. I will still ride it but this will be the last trip away from home.

Pros: I love the CVT drive because there is no shifting. No clutch means I can ride around with a cup of coffee in my left hand. My streamlined Helix meets all the "Vetter Conditions" demonstrating it can be done. This bike has certainly become my first choice among my vehicles to ride.

Cons: The CVT drive. Streamlining allowed re-gearing to slow the engine down, producing the fantastic mileage. But it took special, custom made gears to do this. And, the custom gears have failed. The engine could be slowed more for better economy but acceleration would be too compromised. Somebody needs to make a set of bigger diameter pulleys to broaden the power range. This would solve the problems I encountered.

Well, it wouldn't solve all the problems. I really wanted to ride this machine cross country... hopefully to Alaska. The 10" wheel at the rear and a 12" wheel at the front are too small for the ruts I am told to expect on the way north. The small wheels will keep my streamlined Helix from being a good cross-country machine.

*I post these numbers for reference. Since I DNF'd, you could make the argument that I don't belong among the winners.

230 cc Streamlined Honda CRF
Fourth: 1.59 gallon $4.61
Craig comments:

David Edwards, Editor at Cycle World, was amazed at the mileage and performance of the Honda CRF 230. I passed this information on to Alan Smith when he wanted to build his own high mileage streamliner. The performance of my Helix and the CRF are so similar, I figured they have the same power. Compare the two charts. It is true. Alan burns less fuel downwind but I beat him into the wind. I suspect that when he perfects his streamlining he will do much better into the winds.

Pros: Big wheels. 6 speeds. Chain and sprockets means gearing can be easily altered. Honda reliability. Great starting mileage. Seems to have the correct power.

Cons: Very high seat will make streamlining difficult. Same problem as on the Hayes Diesel. Air cooled engine is proving to be a problem for Alan. He has to spray water on the cylinder to keep it cool in extreme running. Can't drink coffee and ride. Alan cannot carry four bags of groceries.

400cc Suzuki DRZ 400
Fifth: 2.8 gallon $8.49
Craig comments:

Of course Henry did not expect to set mileage records. He rode for fun and to learn. Henry rode 7,000 miles around the US on this bike last summer.... outfitted like this... like most bikers ride. Most riders don't give much thought to how the air passes around their motorcycles. Most riders don't even get 44 mpg!

But, as you can see, streamlining can cut the fuel use in half compared to Henry and his DRZ.

Certainly, this is dramatic evidence of the value of streamlining.

What happened to Charles Bugni?
Charles was there with his KLR 250, full of tricks. But he was missing a muffler and decided to not cause us any trouble with the CHP. Wisely, he stayed behind. I suspect that we will be seing more of him if we do this again.
Notes from October 9, 2010 Challenge:

My top speed - tail wind or no wind is 82 mph, a bit faster than the CRF. I am probably stopped by some kind of rev limiter. Alan is probably limited by his incomplete bodywork.

Last June, downwind, my Helix got 82 mpg vs Alan's 89 mpg. I beat him easily returning into the winds which had gotten much stronger by the afternoon. The winds were stronger both ways that day in June. I am amazed at the great numbers the CFR gets. Today's results are consistent.

The Oct 9th Challenge:

Oct 9: 3 PM Saturday afternoon five bikes headed north from SLO. The winds Saturday were a little different from "normal" and not so extreme. Beginning at SLO, we faced a 20 mph headwind, dying down as we approached Templeton. Then 6-12 headwind to San Ardo. Fierce, 35 mph headwinds (briefly) at the posted speed of 70 mph south of King City.

After King City the headwinds to Salinas were not so extreme... closer to 20-25 instead of the usual 30-40 mph headwinds. A few miles north of King City my Helix broke. We put it into the Hayes chase truck, took it home and carefully filled it with a graduated cylinder.

Compare this to our June 19 2010 challenge when the headwinds were much stronger.

Compare this to a similar Ride Jan 1, 2009.

What is next?
Jan Vos said not to worry. He would make up a new set of gears guaranteed to not come apart. Best of all, they will slow my Helix engine down even more, meaning I will consume even less energy.

It is not over! Jump to Chapter 41

Page posted Oct 12, 2010

Updated Nov 3, 2011