On October 14, 2022, about 1443 mountain standard time, an experimental amateur-built Quickie QII airplane, Canadian registration C-GDHK, was substantially damaged when it was involved in an accident near Laramie, Wyoming. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, during the climb out from the Laramie Regional Airport (LAR), Laramie, Wyoming, a partial power loss occurred. The pilot verified that the fuel system, ignition, and carburetor heat were functioning, but could not restart the engine. Unable to maintain altitude, the pilot determined that the highway was the safest location to land. Upon touchdown, the airplane bounced, veered left off the paved lane, and came to rest upright in an adjacent ditch. The right canard separated, and the fuselage sustained substantial damage. Examination of the airframe revealed no mechanical malfunctions or failures that would have precluded normal operation. Flight control continuity was confirmed from all primary flight control surfaces to the controls in the cockpit. Throttle, mixture, and carburetor heat continuity were confirmed. Examination of the engine revealed the No. 4 top spark plug insulator was cracked, and the spark plug was bent about 10°. A valvetrain continuity check revealed that the No. 1 cylinder exhaust valve was lodged in the open position despite the use of moderate force. Examination of the No. 1 cylinder exhaust valve revealed a dark colored deposit on the valve stem, consistent with carbon, and a slight bend to the stem. Examination of the engine maintenance logbooks revealed that about 5 months before the accident, new engine cylinder heads, including valves and valve guides, were installed, and an annual inspection was performed.