The GM Lean Machine was a concept car built in 1982. It could accelerate from 0-60 miles per hour in 6.4 seconds, and could travel up to 200 miles per gallon. With one wheel in front, two wheels in back, and a closed cabin made of fiberglass and plastic, General Motors planned not to make the Lean Machine resemble a motorcycle in too many ways, and avoided the requirement of propping the vehicle upward with a bar by adding an extra wheel at the rear. The elongated passenger pod, pivoting at either end above the power pod, rotated horizontally and separately from the lower body unit.

Pedals controlled the rotation, enabling the driver to lean into a turn as motorcyclists do to move inward with the center of gravity. The passenger compartment included protection during adverse weather conditions. Steering, braking, and throttle controls were combined in handlebars while an automatic transmission linked to a rear-mounted, liquid-cooled, 30-horse power engine shifted gears.

For the futuristic 1993 movie "Demolition Man" starring Sylvestor Stalone and Wesley Snipes the GM Lean Machine was one of seventeen concept cars produced by General Motors to be featured in the film with an insurance value of $69 million.