On September 29, 2007, about 1315 Pacific daylight time, a Luscombe 8E, N2826K, ground looped during landing rollout at the Ramona Airport, Ramona, California. The student pilot owned and operated the airplane, and it was substantially damaged during the solo instructional flight. Visual meteorological conditions prevailed at the time, and no flight plan had been filed. The student pilot was not injured. The flight was performed under the provisions of 14 CFR Part 91, and it originated from Ramona about 1300. The pilot reported to the National Transportation Safety Board investigator that he landed on runway 27, and his certified flight instructor exited the airplane. The pilot planned to practice takeoffs and landings, and his first flight around the traffic pattern was uneventful. During the second landing rollout the airplane veered off the runway, and a wing impacted the ground and broke. The Federal Aviation Administration (FAA) coordinator examined the airplane and reported that the left wheel had been replaced in 1950 with an incorrect part. The bolt holes were observed to be different sizes for each half of the wheel. The FAA coordinator stated that during operation of the airplane in subsequent years, the through bolt that holds the wheel halves together sheared. This "bolt became lodged in the brake caliper and caused the left wheel to lock up" during rollout.