On August 10, 1997, about 1130 eastern daylight time, a homebuilt Avid Flyer, N7156X, was substantially damaged during a forced landing to a road near Westerly, Rhode Island. The certificated private pilot and passenger received minor injuries. Visual meteorological conditions prevailed for the flight that departed the Groton New London Airport, (GON) Groton Connecticut, destined for Westerly State Airport (WST), Westerly, Rhode Island. No flight plan was filed for the personal flight conducted under 14 CFR Part 91. During a telephone interview, the pilot stated that the airplane was built over a period of 2 1/2 years, and that the airplane was not equipped with fuel gages. The fuel tanks were constructed of fiberglass and contained a 5 gallon mark inside the tanks. According to the pilot/owner, the engine burned approximately 3.5 gallons of fuel per hour in cruise flight at 80 miles per hour. Prior to the first departure from WST, the pilot determined he had 8 gallons of fuel, and approximated 2.5 hours of fuel endurance. The pilot stated he performed 3 full stop landings at different airports while en route to WST. While on final approach at WST, the pilot advanced the throttle to the forward position, and the engine lost power. The pilot determined he would not make the runway, retracted the flaps, and maneuvered the airplane through trees for landing on a road. The right main landing gear separated at ground contact and the airplane came to rest approximately 80 feet past the point of touchdown. Examination by an FAA Inspector revealed that the fuel system was intact and that there was no evidence of fuel or fuel spillage at the scene. The pilot reported to the Inspector that the flight was 1.8 hours in duration. He said he did not account for the additional landings, mismanaged his fuel, and exhausted his fuel supply. The pilot reported 294 hours of flight experience and did not report any mechanical malfunctions with the airplane.