On July 23, 2016, about 1113 Pacific daylight time, an experimental amateur-built Swartz Gene, Titan T-51 Mustang, N5103, sustained substantial damage during a forced landing after a reported loss of engine power while on downwind at the General William J Fox Airfield (WJF) Lancaster, California. The private pilot and passenger were not injured. The airplane was registered to and operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed, and no flight plan was filed. The local flight departed WJF about 1040. According to the pilot, the airplane was about 1,000 ft above ground level, initiating the base turn to final, when the engine lost power. He quickly attempted an engine restart but was unsuccessful and decided to land on a nearby road. He selected full flaps over the road and landed hard. Subsequently during the landing roll, the airplane's right main landing gear collapsed, causing the airplane to veer to the right and strike a highway traffic sign, which resulted in substantial damage to the right wing. Postaccident examination of the airplane's engine, under the supervision of a Federal Aviation Administration inspector, revealed that while accessing the engine, a loose portion of a bolt was observed at the bottom of the cowling. It was determined that the loose bolt portion came from the timing pickup bracket that secures the primary and secondary electronic ignition pickups to the engine. The magnetic flywheel, a part of the ignition system, consisted of four magnets. One magnet became loose and backed out and then struck the secondary timing pickup. Markings were consistent with the impact. The impact force on the secondary timing pickup caused one of the two bolts on the support bracket to separate and break off. Subsequently, the bracket moved about 2 inches, to the right and aft, which effected the primary and secondary ignition system's timing and rendered them inoperative. The broken bolt was replaced and the attachment bracket was secured back into it's support. The engine started and ran on the primary ignition system with no anomalies noted. However, on the secondary ignition system, the engine could not be started due to the damage sustained to the secondary system.