Flying Cucumber 2011

Flying Cucumber 2011

A Speedbike project by Larry Lem
2010 Cyclops was designed to fit a large rider. The 2011 Flying Cucumber was designed to fit Larry Lem.
Cyclops: 170 mm crankarms, 20"-wide shoulders
Flying Cucumber: 150 mm crankarms, 17"-wide shoulders

Two fiberglass layups from the Cyclops top female mold to become the Cucumber plug. Each weighs 20 lb with 6 layers of 10 oz fiberglass cloth and 1.5 gallons of epoxy.
Marked to remove 3" in width. The Cyclops nose profile will remain unchanged so as not to compromise the view out the front.
One top sectioned, the other top marked. 3/4" height removed at the noses from each.
Adding Bondo to blend the sides
I tried to limit the amount of Bondo but still used over 10 gallons.
Top of plug finished, primered. I had to make the top crash panel and top female mold before I flipped the plug upside-down as the plug would not be able to support itself resting on the wheel fairings.
Layup of top crash panel.
Comparison of Cyclops and Cucumber top crash panels.
Top fairing female molds, left to right, 2011 Cucumber, 2010 Cyclops, 2009 Scimitar.
Attaching a bottom wheel fairing section from Cyclops to the Cucumber plug.
Positioning and alignment of the wheel fairings was difficult.
Blending the body with the wheel fairings using plywood. Scimitar was a pod with wheel fairings. The transition of the pod to the rear wheel fairing may have significantly contributed to the drag. For Cyclops, I began blending this area, for Cucumber, I completely blended this area.
Bottom of plug finished, primered.
Top and bottom crash panels.
Cyclops bike in Cucumber bottom fairing. My toes, heels, and knees all brushed the fairing, and the angle was still a bit steep for viewing out the front.
Rather than modify the fairings, I decided it would be better to modify the plug and make a new bottom mold. I removed 1.5" from the rear wheel fairing and added 1" in height to the front wheel fairing to change the overall angle of the bike. I added 1" to the height of the body at the nose, tapering to 0" at the rear to provide pedaling clearance.
Destruction of the first Cucumber bottom female mold.
Sweatshirts get covered in epoxy.
New Cucumber bike side-by-side with Cyclops bike
Making an 8-foot long tab for joining the top and bottom fairings
I had to guess at how to cut a windshield from a Windwrap fairing and unfortunately chose a section that was too "flat".
I ordered another fairing and puzzled as to how to select the best area. I could see easily making the same mistake. I could not fit the windshield into the inside of the top fairing.
And I could not fit the windshield over the top of the fairing very well, either.
Bright idea: I made a mock windshield from the female mold.
It fits the fairing perfectly since it came from the same mold.
I placed the fiberglass windshield mockup over the Windwrap fairing to find a matching section.
The windshield fits remarkably well.
Attaching a vent port to the nose using 2-part urethane foam. I'll use a vacuum cleaner hose to route air to the rider's chin.
Tom Amick testing the bike, test day #1.
Full fairing test, test day #1.
View from chase vehicle, test day #1.
Launch cart with adjustable-height wheels.
Front wheel stabilizer to eliminate some minor steering shake experienced during the first test.
Test day #2
Holding the launch cart allowed one to push but the two-wheel design also made separating the cart from the vehicle very awkward.
Due to many frustrating crashes during launch, we wore through the fiberglass and into the Kevlar portion of the crash panels.
British Racing Green…..was supposed to be Vibrant Lime Green.
The new bottom fairing resulted in more room than expected allowing me to sit more upright and install 160 mm cranks.
Ready for Battle Mountain
The launch cart process was not reliable so we abandoned it. Rick from the Dutch Delft team steadied the vehicle wearing in-line skates and a pusher provided some propulsion to about 10 mph. When we used a skater for launch stabilization with Beluga 5 years ago, the added weight of the skater made acceleration difficult. The pusher solved that problem. Photo by Dave Larrington
Catch area, Monday qual. Photo by Steve Copeland
Catch Tue morning, Tom Amick. I was "extremely disappointed" that the first runs were only 60 mph. I was expecting 70 mph. Rider effort was good but the effort required to exceed 60 mph was much greater than it should have been. Photo by Adam Ince.
Wed photo shoot for the Streamliner Scale Sizing Project at the Battle Mountain Civic Center. Photo by Jan-Marcel van Dijken
Wed night run, Larry Lem. As the air intake hole was located a few inches below the nose of the vehicle, we thought it might be causing excessive drag. We plugged and smoothed the air vent hole but speeds did not improve. Tom and I both questioned whether we were receiving enough fresh air as we were now relying on air circulating from the wheel holes. Photo by Dave Larrington
Wed night run, Larry Lem. Photo by Adam Ince
We didn't know if lack of rider power or high vehicle drag were causing the slow speeds. For Friday, we installed a PowerTap wheel to check rider power. We hadn't used this earlier as PowerTap hubs do not record above 57 mph (700C), and we didn't expect to be going that slow for very long.
Fri morning run, Tom Amick. Rick wasn't available, so we hand-launched - successfully! We also added white yarn tufts to visualize the flow on the vehicle. The tufts looked fine. Tom had to slow for a stopped Barclay Henry (fogged windshield), and then the Cucumber windshield proceeded to fog, becoming opaque. Tom managed to use the side windows to complete his run. He only knew he was in the catch area when he saw a person in a safety vest go by and heard people yelling for him to stop. Photo by Dave Larrington
Fri morning run, Larry Lem. We removed the forward tufts to concentrate on the rear of the bike. The tufts looked fine, but rider power was abysmal. I tried to hold 200 W from the start to the 1 mile sign, but began to labor at the 3 mile sign and was likely down to 150 W at 1 mile to go. I sprinted from that point only raising power to 300 W and then completely gassed 20 seconds later at the 1 kilometer mark. I barely turned over the pedals to the finish probably holding 50 W for the last kilometer. Conclusion: we were lacking adequate air. Interestingly, perceived effort was exactly the same as if there was plenty of air. One cannot rely on perceived effort as an indicator of power unless all other variables are accounted for. Photo by Dave Larrington

For the final runs on Saturday, we reconnected the air hose. Power returned though speeds were still slow. I started the run in the low 200 W range and had to restrict my effort as my legs felt fine and wanted to push harder. Though only at 54 mph at the 1 mile mark, I was reluctant to begin my sprint knowing what happened the previous day. At the kilo sign I pushed above 500 W, counted to 30, glanced at one of the computers reading 59.2 as I entered the trap and exited at 59.9 mph at 400 W. Clearly, I should have started sprinting at the 1 mile mark and could have pushed harder during the run-up to the 1 mile sign.

I wasn't paying attention to the computers at the start and had to wake them up around the 5 mile mark. The PowerTap became erratic with 0.5 miles to go, stopped recording at 0.3 miles to go, resuming 0.2 miles after the finish. In the graph, the power data is from the PowerTap, the remaining data is from the Garmin 500.

If I were to run this vehicle in 2012, I would plug the nose and develop a breathing system. I'd also install the new Garmin Vector power meter pedals and remount the windshield and side windows to make them more flush with the body.

But this vehicle is a little large for me. If I retained this riding position, I could move the rear wheel forward a few inches and shorten the tail, and I could shorten and lower the point of the nose. As the view out the front was fine, I could also cut a pie wedge out of the vehicle when viewed from the top, making the vehicle 2" narrower at the nose, tapering to 0" at my shoulders.

We shall see what surprises 2012 brings.

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