Recumbent Practical fairing
Practical Fairing for the
Electric Assist Recumbent Bicycle

By Warren Beauchamp

While the 450 watt motor in my commuter bike does fine when the road is flat, there is no head wind, and it's warm out, changes in these factors quickly reduce the speeds of the bike. Add in heavy winter clothing and cold stiff tires and speeds drop even further. What's the answer? Either lots of power, or better aerodynamics.
The practical fairing is a great solution, because it will both help the top end speeds, and allow me to commute in the cold weather without freezing by posterior. Fortunately I have parts left over from my old practical fairing, the old MOAT tailbox, and the last WISIL Bubble.

Here's the bubble nosecone and some coroplast side panels, held on with duct tape to figure out precise positioning.

Here's the old MOAT fairing stuck on the back. It will still take some work to attach everything, but much of the fairing has already been completed. Right now the fairing parts are held on with bubble gum.
To attach the tailbox to the bike, I'm using using two 7/8" OD thin wall aluminum tubes tubes wire tied to the rack. The tubes slide into these 1" OD square tubes. I cut sections of the square tube in L brackets and pop riveted them onto the sides of the tube to attach the assembly to the Coroplast fairing.
In this peek inside the MOAT tailbox, you can see the aluminum tube inserted into the bracket. The bracket is pop-riveted to the Coroplast fairing. This will both support the fairing, and allow it to be easily removed.
I wanted to do a test ride with and without the tailbox to see how much just having a tailbox helps the top end speed with the electric motor. Sounds like good experiment, right? So I take the bike out on our little road and find it takes longer than the road is (about 2 blocks) for the little e-motor to get the bike up to max speed. Then I notice the human power chain is off and have to fix that in the middle of the road with my neighbors coming home from work. Ok, that's fixed and I take off with human and e-power to see what the max speed is. Getting near to 30 MPH and approaching a lady walking her dog and... the tailbox rips off and falls on the ground. Hmm. I gave that up for the night and retired to the garage. I'm sure all my neighbors are very impressed. Lesson learned - make sure to properly fasten body parts before testing.
I'm employing the usual technique for attaching the Coroplast panels. I poke holes with a small screwdriver then stitch it together with small plastic wire ties. Once it's done I will cover the seams with yellow electrical tape.
I bent up some aluminum strap into a big U shape and pop-riveted it to the fairing sides to provide the top Coroplast strips support by the handlebars.
Top front is now done. Next I will cut a door in the left side and add some strips on the bottom.

I think I still have the door hinges and latches from the old practical fairing.

Here's the door in the open position. In this picture you can see the latches that keep the door shut.
Here's the door in the closed position. There is lots of room for me to squeeze into the fairing.

I took it for a test ride and other then freezing my head, it went well, with no Coroplast strewn in my trail. Top speeds on the flat were 29.7 MPH, at about 35 degrees F, which is about a 5 MPH improvement over the bare bike - cold weather speeds.

I added a wind deflector to push the air up over my torso. Hopefully this will fix the cold chest issue. I'm still tweaking the Coroplast under the bike to minimize the big hole down there.

Once we get rid of the current batch of snow and the roads are dry again, it will be time to attempt a cold weather commute!

One month later and we have been getting snow practically every other day. I did have a chance to build a super bright LED Light for the bike, which I will mount inside the clear nose. I will paint the nose yellow when it gets warm enough to do that, and leave a hole for the light to shine through.

This past week we had a couple of nice days and I decided to take the faired e-bent on it's maiden voyage to work and back. The morning commute went fine. The bike handled well and I felt comfortable in the fairing. Despite temps in the mid 40s F, I was cruising at about 30 MPH on the flats, a bit more down the hills. 30 MPH is about the max for the electric motor, but now I can go a bit faster with some human power. Without the fairing on days below 50 degrees without the fairing, speeds were closer to 24MPH.

On the way home from work, the winds had picked up considerably. They were now gusting to 30+ MPH, and cats and small children were being blown through the air. In one section of normally busy road I was blown across two lanes of traffic while leaning heavily into the wind. Fortunately there were no cars at the time. On the plus side, the majority of the ride was straight into the wind, where through white knuckled diligence, I was able to maintain a speed close to 30 MPH.

The fairing definitely does what I wanted, which is get my underpowered e-bike to perform in wind and cold weather, but remind me to leave it home when the winds get crazy like today. Wow! what a ride...

I had a long and pleasant ride on the faired e-bike over the weekend. I think I rode about 50 miles (speedometer was not working). I pedaled most of the way, just using the electric power to help up steep inclines. It was pleasant. I also commuted to work once this week in temperatures around 40 degrees F. I was able to ride with just a windbreaker, and stayed plenty warm. While the winds riding home were blowing, I had no problems with handling. I just have to remember to stay off the roads on the days when they issue wind advisories.

Here's the LED light mounted in the nose of the fairing. I still need to wire it up to the 24V e-bike battery.
This fairing worked great to make the most of my human power and the power from the electric motor, but I had a couple good scares being blown around on the road in high winds. I really did not want to be blown into to traffic, or off into the ditch, so I removed the fairing. I upgraded the e-bike with a more powerful drive system and now I laugh at the wind. The cold air is another problem. Eventually I hope to have a faired trike as they handle the side winds better, but I have not come up with a design that I feel will co-exist with the car traffic yet.


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