On January 5, 2008, about 1700 Pacific standard time (PST), an experimental Rowland GS-2 Sport, N756R, collided with a fence during a forced landing near Ramona, California. The pilot was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The airline transport pilot was not injured; the airplane sustained substantial damage to the elevator. The local personal maintenance test flight departed Ramona about 1630. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that the purpose of the local flight was to determine the cause of high oil temperature in normal cruise flight configuration. Prior to the flight, the pilot had made an adjustment to the fuel servo. During the flight the engine temperature was increasing and the engine subsequently lost power. The pilot was unable to restart the engine and he initiated a forced landing to a dirt airstrip. Due to a high rate of descent and headwind, the pilot was unable to land at the airstrip and he diverted to an open field. During the landing rollout, the airplane collided with a fence. The tail and elevator struck the fence and sustained substantial damage. A Federal Aviation Administration (FAA) inspector examined the airplane after it had been recovered. The inspector stated that other than an initial fuel rich condition, the engine started and ran normally. After a brief warm up and increased rpm, the engine smoothed out. The mixture was leaned and the engine ran smoothly and responded well to throttle changes. During idle, the mixture was pulled to the "cutoff" position and the rpm increase seemed normal. The inspector reported that an attempt was made to restart the engine with the mixture full rich, but it would not start. A hot engine start procedure was used (mixture positioned at cutoff), and the engine started with no problem. No other abnormalities were found which would preclude normal operation. The pilot reported a total of 23.8 hours of flight testing at the time of the loss of engine power.