The low end of CdA -- Wow, I want one

[The Toecutter]

Ever since I saw it, I've always wondered what could happen if the Quattrovelo lost its pedals and was turned into a titanium-framed car with a carbon fiber/kevlar body and scaled up to accomodate a second passenger. Say, a tandem two seater with a 0.7 sq m frontal area, set up with all wheel drive via an in-wheel hub motor on each wheel of about 50 kW each with thick, sticky motorcycle tires, vector control, and a 10 kWh pack of Lone Star batteries?

You'd end up with a vehicle that weighed around 450-500 lbs unladen, had a CdA of around 0.15 m^2, and need like 2 kW to do 60 mph. Gear it for 120 mph(it probably wouldn't be stable after that), and its acceleration might match the new Tesla Roadster in all of its operating points... and you'd have well over 200 miles range driving on the highway for far less expense than it would cost to make a Tesla Roadster...

[freebeard]

Basalt is equal to carbon-fiber or Kevlar. One would hang subframes on a monocoque. Titanium performance could be equaled at lower cost by foamed steel or aluminum extruded through a 3D printer.

3-wheel steering 3-wheel drive with something similar to the Copenhagen wheel.

edit:
http://www.bikeexif.com/ducati-monster-400-cafe-racer

[Ecky]

Originally Posted by freebeard

Basalt is equal to carbon-fiber or Kevlar. One would hang subframes on a monocoque. Titanium performance could be equaled at lower cost by foamed steel or aluminum extruded through a 3D printer.

3-wheel steering 3-wheel drive with something similar to the Copenhagen wheel.

edit:
Stone Cold Crazy: A Ducati Monster Wrapped in Basalt | Bike EXIF

My velo uses a geared hub motor. It's capable of ~5000RPM before gear reduction (approx 5:1) and very reliably produces ~3000w or 4HP for short bursts, probably half of that continuous without any cooling.




Geared hub motors can't do regen because the planetary gearset allows them to freewheel, but tend to be more efficient than direct drive motors because they don't need ridiculously large (and heavy) windings to operate efficiently in the RPM range wheels typically spin at. Above maybe 3-4HP, cooling them is problematic though.

[Xist]

Originally Posted by freebeard

I had to wear two pair of sunglasses.

Did you remove them dramatically?

I am thinking of Humpty Hump from "Nothing but Trouble," but that was a disappointing movie.