As one sees ideas being developed one must remember they have all been tried before. Same with three-wheelers. Three wheel vehicles with two wheels up front and one trailing have been around since the earliest days of automobiles. Their history has been on-again, off-again, and mostly off.
This is for a very good reason, not some deep dark conspiracy. Two-forward three wheelers are treacherous in a corner. They tend to swap ends really easily. One tire does not have the lateral traction of two. Worse yet, the zero camber of a single rear tire gives it no mechanical advantage over the tendency of a vehicle to “throw” its rear end around in even moderate-g turns.
I look at this design and I see a second mistake – engine in the rear. This exacerbates the tendency the throw the rear end around as now the weight of the engine is added to that force.
One of the very few (sorta) successful three wheelers was the British Morgan, built during the Great Depression The car had an air-cooled 45 degree V-twin mounted exposed in front axle. The car looked for all the world like a somebody in a three-wheeled MGA had t-boned a Harley-Davidson.
http://rides.webshots.com/photo/2588...98837763rCjmXx
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That V-twin engine actually drove the rear wheel through a drive shaft. The Morgan was actually fairly successful because the engine was forward of the yaw axis and tended to resist the three-wheelers tendency to ground loop.
I don’t mean to discourage the idea of a two-forward three wheeler. It is an efficient idea. But I cannot imagine anything more discouraging than having to sit in your wrecked three wheeler whilst some fireman uses an emergency grinder to cut through your tube frame to extract you. Damage control always starts with avoiding a wreck.
If it were me, I would approach this somewhat differently. I would start with a VW TDI engine/transaxle and a vehicle about 60% the width of a Golf/Jetta. All the drive train and suspension issues have been worked out over decades of development. Front wheel drive is old hat in this day and age. My passenger compartment would be a tandem seating arrangement with a fairly upright seating position. An upright seating position gives you a very comfortable ride and you have to be able to see over the engine compartment. At the back I don’t use one tire but rather two skinny tires set at about a 2 degree camber. The rear wheels have a much narrower track than the front, allowing a very nice aero shape. With this setup, you get all the aerodynamic excellence of the three wheeler without driving a ground loop waiting to happen.