Brad Teubner builds a Recumbent Velomobile
Building the Orange II Velomobile  

By Brad Teubner

4/20/08
I’ve got over twenty miles on the new trike, so it is time to publish the results and claim success. I intend to paint it eventually, and the raw materials for an orange fairing are on hand.

The plan was to build a "best of" several other bikes/trikes that I own or have owned. It was sketched out in a simple CAD program, and parts fabricated from there.
 
It has a Ross seat and eventually, it will be faired similarly to my Speed Ross. My Ross is the fastest and most comfortable bike I've ever owned.
I simplified the Orange Varna geometry and driveline. Ray Brick did an incredible job designing that driveline, and I didn’t fully appreciate his efforts until I started trying to do something similar except simpler.

The ergonomics copy my M5. (Fastest unfaired bike I've ever owned.)
The main tube is a mandrel bent piece of 2"OD 0.055 wall muffler tubing at 8 lbs 2 oz with head tube welded in.

The company that bent the tubing could bend a 3” radius center-line bend, so all of the bends are that radius to simplify their work.

The head tube is the only part welded to the main tube; everything else clamps and so can be adjusted. (I’ve learned that my simple computer models just aren’t good enough to cover all of the variables.) 

 

Bottom bracket clamp is a double clamp. It adjusts front-back along the frame, and also allows me to slide the BB shell left-right.
 

 

Mid drive bearing housing clamp is also a double clamp. It adjusts front-back along the frame, and allows me to slide the bearing housing left-right.

Front seat mount slides front-back along the frame. Rear seat mount is an aluminum bracket held with hose clamps. I may move the rear of the seat down another inch.
Rear axle mount slides front-back along the frame.
The chain idlers are also clamps and can be adjusted. 
 The rear axle is a 1x1x36" steel with a rounded front and trailing rear welded to it. 4 lb 6 oz without wheels.

One thing I noticed during assembly (with no chains on the trike) that you probably wouldn't with a bicycle: I had the shoes clipped into the pedals (without my feet), and when I raised one heel and dropped it, the shoe rocked on the crank, the crank rocked on the frame, and the trike rocked back and forth about 1/2 inch on the floor. Low rolling resistance; love it. When I spun both shoes, the motions become very complex.
 Weight of 39 lbs using the bathroom scale
((me+bike)-me) method. Not too bad for a mild steel frame tricycle. Weight distribution with me on the bike is 55% front, 45% rear. This will probably change when the shell is added.

After I get everything tuned in, and am happy with it, I will consider building a lower weight frame. But I'm 20 lbs heavier than I want to be, so hard to justify too much extra time and expense to pull 5 lbs off the trike.

Handling is very quick; I tried to duplicate the front fork angle of the Barcroft fork when used by Barcroft.

Some additional information.

  • Cranks: 150mm 52/48/26. There is some complexity to the idler system to allow the shift to the 26 and everything to clear.
  • Mid-drive: Cut down MTB crank 22/36. It was going to be a 22/32/44, but shifting the 22/32 became a hassle, and the 44 was higher than my knees. So it’s a 22 in, 36 out. I needed the 36 so that the chain would clear the back of the fork.
  • Final cluster: 36/11 9 spd. Overall, 23-143 gear inches. It certainly doesn’t have to be that high-geared for me, but I want to cruise in 17 or 20 tooth final.
  • 406 tires: Stelvio rear, Comet Kevlar front.
  • Front brakes only. Mechanical disc primary, rim back-up.
Idlers are laser-cut discs pop-riveted together over roller blade bearings. Power side has 2 bearings, return side idlers have 1 each.
Building a Nosecone for Orange II
The most difficult part of building a street fairing is finding a nosecone of the correct size for a reasonable price. It is fairly easy to do simple curves at home, but compound curves are more difficult. (I have been trying to talk some college person with CFD access and time to design a 4-petal nosecone for decades with no success.)
6/06/08
Finished nosecone on trike. The orange Coroplast fairing body to follow is in the preliminary design stage. 
Detail to show tip mechanism for entry/egress. 
Start with a 24” OD plastic hemisphere from pr-tech.com. (More info on P & R Technologies at the end of the article.)
Cut off the parts you don’t want. 
 
Force it into the shape you want in a mold and put it in your cardboard oven. (Ace heat gun with circulating fan and Watlow temperature control)
 
Cover the oven and heat at 200F for 1 hour. This is enough heat to allow the plastic to relax to its forced shape.
 
Recognize the error of having your circulating fan in the output of the heat gun so the blade comes off. Temperature was controlled to 200F at the bottom, but the top must have gotten much hotter.
 
Redesign the mold so you can reverse the sag. (250F for 1 hour) 
Nosecone out of mold. I practiced on two 20” hemispheres, and did one 24” that is good enough for my winter work trike, and one fairly nice 24” that I’m putting on Orange II
 
Design an attachment to the die grinder so that you can cut 0.075” off of the trailing edge at 15 degrees. After that the trailing edge was wet-sanded with 280 grit to break the hard edge and remove the router ripples. I plan to attach the 2mm Coroplast to the inside of the nosecone in a method to-be-determined. Probably zip ties but possibly pop rivets. 
P & R TECHNOLOGIES make plastic hemispheres in a number of diameters. These are the spheres that you see hanging on power-lines for aircraft warning, so they are durable, and made in a number of colors. Colleen was very helpful and friendly, and they will sell the spheres for $100/sphere (20”) and $130/sphere (24”) plus shipping. A sphere is two hemispheres. Be certain to specify that you do not want drainage holes, and you do not need power-line mounting hardware.
Information at http://www.pr-tech.com/products/markers/spanguard/spanguard-order.htm

Colleen Jackson
P & R TECHNOLOGIES
503.292.8682 phone
503.292.8697 fax
503.730.3534 mobile
colleen@prtech-pdx.com
www.pr-tech.com
 

This picture triggered the humor:
Q: "What do you do at work, Daddy?”
A: "Not much. I just sit around and bolt pieces of plastic together.”
 

9/5/08
Constructing the Coroplast body.

First, I built a half-prototype out of cardboard.
Front view of the Orange II velomobile with carboard fairing template.
Brad and his cardboard fairing template. 

Then it was simply the process of copying that pattern onto 2 sheets of 2mm Coroplast, about a hundred zip ties, and two weeks of evenings and weekends trying to figure out how to get in and out.

Length is 100 inches, wheelbase is 42 inches, overall height is 29 inches 
Track is 39 inches, and nosecone width is 17 inches.  
There is more speed hidden in better sealing around the rear axle and in better closing of the bottom rear.  But I still need to be able to get in and out.
I also plan on improving the flow around the head opening.  There are some limitations in closing the hole up as I need to be able to swing my head to use the helmet mounted mirror, and my eye level is only 1 1/2” above the top surface.

 

 

4/02/2010
More development on the O2 (oh-two).

I have about 1900 miles (3000 km) on the chassis, and about 800 miles (1250 km) on the shell detailed below. My last run this spring was an average speed of 21.56 mph (34.7 km/h) for an out-and-back of 40 miles (64 km). I estimate my power output at 130 watts (0.175 horsepower).

Pounds

Left

Right

Front

Total

Empty

14

14

32

60

BT+ tools

59

58

128

245

Camp Ready

77

81

121

279

 

 

 

 

 

Kilograms

Left

Right

Front

Total

Empty

6.4

6.4

14.5

27.2

BT+ tools

26.8

26.3

58.1

111.2

Camp Ready

35.0

36.8

54.9

126.7

 

 

I decided to make the trike into a touring vehicle, and wanted more storage, so the shell was rebuilt over the July 4 vacation of 2009. The first goal was to make a large tailbox, and a 4 foot (1.22 meter) long aluminum I-beam was fabricated for the base.
 


The ribs are lawn chair aluminum with the recycled Coroplast attached with plastic “Christmas tree” clips
The sides and top are rather easily removable as a unit (1/4 turn plastic Dzus fasteners)

Storage volume is estimated at over 8000 cubic inches (130 liters) in the tailbox with another 1000 cubic inches (16 liters) useable on the floor in front of the tailbox enclosure. Here is a 5 gallon (19 liter) jerry can sitting in the tailbox for reference.
Vehicle with the front open
Here is the view you seldom see of enclosed bikes.
And various profile views. 

Front.
Side
Back
Below are added bits that may be of interest. Note the parking brake and the speedometer mount.
Handlebar cluster, top.
Handlebar cluster, front.
I do have rear wheel fairings fabricated, and did some very preliminary testing last summer without great success. I was not able to get them to hold shape well, and I didn’t see a noticeable speed gain.
When I can find a way to hold the fairings on the outside of the wheel that still allows easy service, I will continue the testing.

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