Larry Lem builds the Beluga Speedbike
Larry Lem builds the Beluga Speedbike
A project by Larry Lem
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This was my first try at building a streamliner, so I thought I'd build a fairing in pieces. This would allow me to work with relatively small parts and maybe keep the scale of my mistakes small as well. My initial goal was to race at Fiesta Island, San Diego, California. A 20 km TT is held there, the course is flat, and the slowest turn can be taken at 30 mph.

The course record is 23:05, set May 21, 2001 by Eric Hollenbeck riding a San Diego State University ASME competition vehicle. Ben Huntley was 3 seconds slower on the same day riding the same vehicle. Dean Pederson chased this record for several years with his Coyote and got very close at 23:06, one second off of the record. I do about 30 min flat on my lowracer with 190 W of power.

Rather than modify my existing lowracer (pictured)which would put it out of commission, I decided to build a new bike. This would be a simple bike with a direct view of the road (no camera system). It would be RWD as I wouldn't need overly large gears for the TT (would not need a middrive). I wanted a lot of steering angle capability as this would be a "beginner's" streamliner. This meant plenty of clearance of the crank, pedals, feet, legs, drivetrain with the front wheel, and a big hourglass cutout for the front wheel.
I experimented with the seat angle until I was satisfied that I would be able to see over my knees. I had to raise the seatback to 45, which was quite upright compared to any of my other bikes. This is the a result of having long legs and a short body. The frame is 4130 steel, 2" OD, .049" wall.

During frame construction, I had my usual problems with alignment, having to cut things apart many times, and cold-bending parts into line after welding.

I also experimented with landing gear. I tried 3 versions for the actuation system, settling for 2 rings and a hook. Photo by Jeff Wills.
I copied a side view photo of myself on the bike onto an MS Excel graph, and plotted the outline of a fairing shape.
Front Fairing Sections
My plan was to make top and bottom front sections, a tailbox, and a top middle section. The canopy would be worked out at the end.

For the top and bottom front plugs, I used plywood as a base and vertical backbone, with bulkheads every 10 inches. I left room for 1/2" of whatever was to cover the plywood.

 

Hot-glued strips of doorskin wood over the plywood bottom plug
Doorskin covered with a layer of fiberglass to prevent Bondo from pushing through the gaps. This step ended up being unnecessary and I didn't repeat it on the top plug.
Pink frosting - applying Bondo to the top section. I spent many weeks sanding, shaping, reapplying, patching the Bondo, tryng to make a smooth, uniform shape
Bondo on front top with primer. 
White painted bottom front plug.
Black painted front top plug. 
I layed up a part off of the bottom plug, losing a lot of paint to the part. I learned that you have to use a lot of wax. (I didn't know about PVA yet.) I also made a top part off of the top front plug.
Cut the front wheel hole, reinforced the hole, built brackets to mount the bottom to the frame and glassed them into the bottom.

I intended to race at Casa Grande in June 07, but the top piece didn't match the bottom very well. The intersection matched as I made the plywood bases for the plugs at the same time, but the surfaces didn't match, despite using external templates when shaping the plugs. I think the problem was that I intended to apply the Bondo at a uniform thickness, but had no real control for that.
Seat and Tailbox
I decided to take a break from the fronts (having spent a few months on them) and work on the tailbox. I planned on using the seat as the attachment point. I used a Swanson seat as a mold and made many iterations, creating a lip on the front, widening the seat, and making it taller, without hitting the back of my helmet. This took a few tries.
I would cover the seat in wax and pull parts off of the front and back. Then I'd sandblast the wax off of the parts, use a couple layers of fiberglass and epoxy in between halves, clamp together and cure. I ended up buying about 100 clamps. I had a lot of trouble supporting the seat, keeping it square when bonding the front and back halves together.
The pad matches a Swanson seat for comparison.
New seat #2.
I attached the seat to the bike, attached some brackets to the seat, and made a frame for the tailbox out of 1/8" x 1/2" flat steel bar. The flat bar only bent in 2-D; this helped keep the right and left sides symmetric.
I left 1/2" for shaping material on the surface. I covered the cage in 1/2" wire cloth, bolting and welding it in place. I covered the wire cloth with a layer of fiberglass.
Fiberglass covered with 2-part expanding foam.
foam shaping 2
I attached the bike to the front bottom test piece and found that I had a major alignment problem with the frame and seat. The tailbox was off by a full inch at the top of the seat compared to the frame and front wheel.
I removed the seat, the tailbox mold, cut the frame, and re-welded it at the downtube with a slight twist to straighten things.
tailbox foam mold2
I intended to cover the foam with a thin layer of Bondo. But in applying and sanding the Bondo, I created thin, weak spots, sanded through the Bondo into the foam in some areas, and had to dig out out foam and apply thicker layers of Bondo. In a few places, I sanded through the fiberglass and had to grind through the wire cloth. So much trying to use 2-part foam.
I spent several months on the tailbox mold. The bike became very heavy. I eventually got frustrated and proclaimed it "finished".
Tailbox plug done.  After completion of the plug, I painted it black, dropped it, cracked it, and patched it. It probably weighed 50 lb and was unwieldy.
 
Next event: Battle Mountain Oct 07.
For Battle Mountain, I decided that I'd want a uniform-shaped fairing which would require large molds, not small molds and disjointed pieces.

I made a female mold from the male plug by first covering the tailbox with lots of wax, then many layers of fiberglass and epoxy. 

To make the female mold stiffer, I hot-glued sections of swimming pool noodles (polyethylene) on the outside.

Glassing over the noodles. 

I cut a parting line in the mold between the top and bottom to remove it. 
Female tailbox mold top and bottom molds done
I made top and bottom tailbox test pieces from the female molds. I set the bottom front and tail together to see how they'd look. They looked like a canoe.
Front fairing sections again.
I decided to put the two front plugs together to see how they matched. This was not easy as they were big and heavy with Bondo. As the top was black, and bottom was white, they looked like the front half of a juvenile killer whale. I had difficulty clamping the two halves together as there was nothing to grab. I used nylon straps around the middle and C-clamps at the back. I cut an inch off the nose to decrease the pointyness.

Continued on Page 2

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