Well, I decided to play with the idea of a bubble canopy. Ideally, I would make the canopy deeper than in the drawing. I am trying to weight the difference between making the rear wheel enclosed vs being open. With the rear wheel being enclosed it makes tire changes and patches more difficult. An open rear tire is more easily changed or repaired and allows for a trailer to be hitched to the rear drop out, but is less aerodynamic.
The dark area around the canopy would be the hatch that would lift up and forward for the operator to enter/exit. I am exploring the idea of having the main frame being wider (20 inches vs 4 inches) then I originally planned and having a sub frame in the middle for the pedals, seat, and rear suspension. A wider frame approach would allow for more side protection in the event of an accident. I could add foam blocks between the frame and the outer shell of the velomobile, like a modern car bumper for side impact protection.
The down side to a canopy is the greenhouse effect. The canopy would have to be painted on the top to block the sun. A canopy could be made with some simple tools. It should yield an aerodynamic shape with little effort.
Open rear wheel would be far less aerodynamic. For example the rear tailbox is more effective than front windshield. Nowadays you can choose tyres like Schwalbe Marathon plus with perfect puncture protection and you can also make some kind of hitch for the trailer which will allow to use it or you can make the shell so it is going a little bit above the rear wheel axle so you can use the trailer.
ReplyDeleteIt is also the reason why Go-One developed the new version with enclosed rear wheel.
Best regards,
Honza
www.recumbent-gallery.eu
Let Quest build you a real velomobile. The one you seem to be planning is going to be inferior in design and higher in cost. The Quest is state of the art, and you can add an electric motor assist with a bike shop crank change ($25.00) and 5 bolts. Mine (286) gets about 2000 mpg if I don't pedal!
ReplyDeleteI agree with the comment that you can buy a better velo than you can build, but not as unique. I'd go ahead with what you're doing and decide when you're done whether a factory-built is better. As for the rear fairing you can have both worlds if you make the tailbox removeable. This will also give you a visceral FEEL of the difference in drag. I tried it on a rough homebuilt about 10 years ago, I never went without one again.
ReplyDeleteNick Hein
Morgantown, WV