The Search for Fuel Economy

Pages from a Designers' Notebook

Nov 4, 2008

The goal: 100 mpg at 70 mph, into a 20 mph headwind, with four bags of groceries. It looks like we'll be calling this the Freedom Machine.
Chap. 20: Streamlining the windshield area
This is a pretty tricky design problem. I am pleased at how it is working out.

The goal is to totally streamline this machine. Streamlining, as you will recall, is a smooth, continuous shape, round at the front, pointed at the rear.

So far, it still ain't streamlined.

The moving handlebar is one of the hardest areas to deal with.

Specifically, I want full, lock-to-lock turning.

Here we deal with the moving handlebars.
I have welded a flat mounting plate onto the handlebars, perpendicular to the axis of turning. On this surface I will build the rotating part of the streamlining - the streamlining that covers my hands.
My granite stone and surface gauges help me to keep things true. After I checked the handlebar for accuracy, I wire brushed it off and spray painted it so it wouldn't rust.
CAD-Cardboard Aided Design bulkhead helps me determine the shape. I also cut away a window so I could see my gauges.
Cutting two, aluminum sides exactly the same, insures symmetry. I left the little circular tab in the center to keep track of where the center is. I cut it off later.

By the way, I am building this thing with very few power tools: A band saw, sabre saw, drill press, 1/4" drill and, 16" disc sander and a 120 v. wire welder. Most of you can do this.

Mounting plate in place

At this point, I shimmed and trimmed until I had a perfect, 1/4" air gap between the moving and non-moving parts. Full steering travel, right and left is guaranteed.

When the wheel is pointed straight forward, the shapes match up. The air will pass by it easily. When the wheel is turned, the handlebar streamlining rotates over the body and does not match up. This is no problem because if the wheel is turned this sharp, you are probably pushing it around the garage and are not going very fast.

I call the opening shape for the turning wheel the "Smiley Face." The smiley face is less pronounced here because of the Helix's small 12" wheel front wheel. The smiley face can also be reduced by limiting the handlebar turning, a solution I won't ever do again. Limiting the handlebar turning makes it too hard to push around the shop.

The Dodge Caravan headlights sure fit better than the stock Helix light

(Note the inflated tail on the floor. It weighs 3 pounds)

Now I can clip strips of aluminum along the sides to help visualize where the streamline surface needs to go. The idea is to make the streamlining on the moving portion (with the handlebars) match up exactly with the non-moving streamlining of the body. The aluminum stringers will be my guide

On days like this, when the Freedom Machine is in my shop, I cannot ride it. I have to ride my backup red Helix. I am getting spoiled by streamlinig.

Time to make a new bulkhead to go around the handlebars. 1 1/4" x .100" aluminum is easy to bend. A drawing helps symmetry. After I am sure it will slip inside the existing loop, I will cover it in yellow plastic streamlining
This is the moment of truth. Will the handlebar bulkhead slip in between the frame bulkhead?
QuickTime Movie of handlebar motion. Don't have QuickTime? Click here for a free download from Apple.
It is now safe to add the plastic sheet streamlining to this new portion. Plastic, barbed push fasteners hold it all together, just like on the rest of the body.

Yeah... I am not happy with this "Approximate Streamlining." It is so "scaley" looking. But it offers the best compromise for quick construction and road testing. Can you imagine trying to do all this on a computer and not taking your first ride until thousands of Freedom Machines were coming off an assembly line?

Riding comments, November 4, 2008:

It is getting colder in Carmel. California, (but it never gets REALLY COLD like it did in Illinois when I lived there.) But with this streamlining, I no longer need gloves. There is simply no air drawing away my body heat. Very satisfying indeed. This is another one of the rewards of good streamlining.

The only wind I get is in my face. I miss the clear windshield and can't wait to replace it with an even better one than before.

The HID lights are blue-ish and not as illuminating. Part of the problem is that the headlights are not aimed exactly right because the front bulkhead is in the way. On a later version, I will angle the bulkhead back a few inches and the problem will be solved.

I am beginning to notice that, as I add streamlining, it is getting harder to get things (groceries, of course) out of the cargo hold. Maybe I can move the rear bulkhead forward on the next version for easier access to the hatch. I am thinking that it might be easier to lift up the side for access.

I am resigned to the fact that this may not be the "Last Vetter Fairing" after all. It is no longer just a fairing. It has become a vehicle with a name:

The Freedom Machine
This page posted Nov. 4, 2008
Chap. 3: Road Testing the Long Tail Mar 28, 08
Chap. 1: Streamlining Saves Fuel Feb 20, 08
Chap.2: CAD Streamlined Body Mar 8, 08
Chap. 4: Planking with Foam Apl. 5, 09
Chap. 5: More Wind Testing Apl. 7, 08
Chap. 6: The Final Shape Apl. 17, 08
Chap. 7: Decisions about Details May 10, 08
Page 8: Making the Center Bulkhead June 1, 08
Chap. 9: Rear Bulkhead and Truck bed June 8, 08
Chap. 10: Finish Rear and go for ride June 17, 08

If you have not yet watched my DVD, How they Got 470 mpg it is time to get it for the basic foundation for what we are doing here

Chap. 11: Finish the Tail June 29, 08
Chap. 12: Heading for Ohio, July 13-23, 08
Introduction to Fuel Economy
Chap. 13: Riding in the Midwest July 24, 08
Chap. 14: Vintage Days Ohio, July 25-7, 08
Chap. 15: Summary to date Aug 12, 08
Chap. 16: Adding Weight to the Front Sep. 1, 08
Chap. 17: Truth and Motorcycle Design Sep 4, 08
Chap. 18: Where should the weight be? Sep 25, 08
Chapter 19: Finishing the Streamlining Oct 14, 08
Chapter 20: Streamlining the Handlebars Nov 4, 08
Chapter 21: Unexpected Problems Nov 11, 08
Chapter 23: Getting my feet in and out Dec 19, 08
Chapter 22: Streamlining is working Nov 25, 08
Chapter 24: Streamlining is beginning to work! Jan 1, 09
Chapter 25: Tuft Testing Mar 2, 2009
Chapter 26: Starting Over April 9, 09
Chapter 27: More Ideas for Starting over April 20, 09
Chapter 28: Show time! Aug 1, 2009
Chapter 29: Getting the big parts right Dec 10, 2009
Chapter 30: First evaluation from an outsider Dec 20, 2009
Chapter 31: Visit with Allert Jacobs Dec 24, 2009
Chapter 32: Prius Headlights Jan 18, 2010
Chapter 33: New Gears Feb 17, 2010
Chapter 34: New Mileage Records April 25, 2010
Chapter 35: The Quail Gathering of Motorcycles May 9, 2010
Chapter 36: End of the line with the Helix June 19, 2010
Chapter 37: Vetter Challenge Oct. 9, 2010
Chapter 38: John Keogh helps out Dec 8, 2010
Chapter 39: Working with Keogh Dec 17, 2010
Chapter 40 and up (Work continuing in 2011)
Designing the Last Vetter Fairing

Chapters 1 thru 39 (2007-2010)

Chapters: 40 thru 51 (2011)

Chapters: 52 thru 61 (2012)

Chapters 62 thru 68 (2013)

Chapters 69-up (2014)