Tilting multi-wheeled vehicles, in particular, tilting three wheeled vehicles with two front wheels are operated like motorcycles where such vehicles lean into a turn. Unlike motorcycles, an added extra wheel in front provides additional traction for improved stopping and control of the vehicle on slippery surfaces. This type of vehicle is usually lighter, and can be made narrower than a non-titling three or four wheeled vehicle.
In the prior art, titling three wheelers have generally been of the straddle type, or having a recumbent seat, where the operator rides the vehicle like a motorcycle and controls the lean by shifting his/her body weight and by practicing counter-steer techniques.
Some patents advocate the utilization of tilt lock or tilt limiting mechanisms and footboards on a non-tilting portion (simulating the ground) where the operator can use these boards to control the lean of the vehicle for added safety and stability. Examples of this type are described in U.S. Pat. No. 4,088,199 to Trautwein and U.S. Pat. No. 7,530,419 to Brudeli.
It has also been known to implement tilt control mechanisms, usually hydraulic, pneumatic, or electro-mechanical actuators, connected between a tilting and non-tilting portion of a tilting vehicle. This type of arrangement simplifies the operation of the vehicle where the rider doesn't need to learn how to operate a free leaning vehicle (motorcycle), and can practice simple steer. Such mechanisms are manually activated by the operator or use some type of pendulum device or an electronic control unit that uses the input from different sensors (such as speed, steering angle, lateral forces, etc.) to control the tilt mechanism without user input. While such arrangements provide acceptable tilt control mechanisms, they do not replicate the exact feeling generated by a free leaning motorcycle or tilting three wheeled vehicle. An example of this type of tilt control is described in U.S. Published Patent Application No. 2009/0312908 to Van Den Brink.
Some have described tilting vehicles having an enclosed or partially enclosed cabin mounted on a titling portion of the frame, having enough space for one or two inline (back to back) seats, and just enough width to accommodate one rider. While this type of enclosure provides better protection to the rider than an open tilting vehicle, it usually is relatively narrow since a wide body would touch the ground even at moderate lean angles. This makes it necessary to design the body with a narrow or rounded bottom thus creating a displeasing aesthetic appearance. Further, a narrow titling vehicle is not as safe as a vehicle that can support a wider frame and enclosure (creating a greater buffer zone between the rider and the frame), at least when it comes to side impact in the case of a collision with another vehicle or in the case of a rollover. An extremely narrow enclosure also limits the ornamental design that can be applied to the completely or partially enclosed tilting vehicle, thus reducing the chance of success in the marketplace.
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