Robert Q. Riley Enterprises says its new plug-in diesel-electric hybrid is two months from launch. (It'll debut on June 16.) Purportedly, the three-wheeled XR-3 will get 125 mpg on its three-cylinder, 23 hp diesel engine alone, and 225 mpg when coupled with an electric motor driving the rear wheel. Riley, a well-known custom car builder and purveyor of kit-car plans, will offer the XR-3 in kit form. For those with more time and talent than reasons just to sit and watch reruns of "Freak Show," the company will offer it as a set of plans only. [UPDATE: Press release after the jump.]

[Reilly XR-3 via Motor Authority]

Kit Car Designer Takes on Hybrids [internal]

Press Release:

Fuel-Efficient XR-3 Will Offer 125-225 Miles per Gallon

In less than 90 days, Robert Q. Riley Enterprises, LLC, a product design firm in Glendale, Ariz., will introduce its XR-3 plug-in hybrid, a sleek two-passenger, three-wheel sports car that is expected to generate up to 225 miles per gallon.


Designed to be assembled by someone with average mechanical abilities and no prior experience, the all-wheel drive vehicle will be available as a kit or plans for complete do-it-yourself construction.

"We've made a technology leap by designing a super-simple hybrid power system, but 'technology' itself was not the main thrust of the project," said Robert Q. Riley, company president and author of "Alternative Cars in the 21st Century." "We focused on the power of 'design' to define a new category of personal mobility products that are neither automobiles nor motorcycles."

The XR-3 uses the latest hybrid power system technologies in the most simplified way possible. While the front wheels are powered by a three-cylinder diesel engine, a single rear wheel uses an electric motor run by a lithium-ion battery. The ground provides the connection between the two systems, eliminating the need for a complex electronic and mechanical interface.


Driving on power from its diesel engine, the XR-3 can achieve fuel economy of 125 miles per gallon. However, when the diesel and electric power systems are combined in a hybrid driving mode, fuel economy can exceed 200 miles per gallon over an 80-mile trip.

A simple three-position switch allows the driver to select between battery-only, diesel-only and hybrid driving modes. The diesel engine can remain off for local trips, since power from the advanced lithium-ion battery pack gives the car a battery-only range of up to 40 miles.

Robert Q. Riley Enterprises, LLC is a full-service product design and development consultancy in Glendale, Ariz., specializing in transportation, recreation, fitness and medical products. For more information, please visit