A 22-year-old man is still in critical condition today after crashing his motorcycle Sunday afternoon on S.D. Highway 44.

Bryant Boeding was riding a 1988 Harley-Davidson motorcycle at about 1:45 p.m. three miles west of Rapid City when he lost control and struck the guard rail.

South Dakota Highway Patrol reports said eyewitnesses saw him standing on the seat of the motorcycle as he rode.

Boeding was not wearing a helmet at the time of the crash. Alcohol was not reported as a factor in the accident.

In an unrelated matter, the Highway Patrol also reported to the scene of a six-car pileup Friday night on I-90 near Exit 60. The Rapid City Police Department had responded to an accident and redirected traffic into the passing lane.

Trevin Smeenk, 29, of Rapid City was riding a motorcycle and struck the back of a Ford Taurus, driven by Amanda Hove, 23, of Pierre. Four vehicles behind Smeenk each rear-ended the vehicle in front of them.

No serious injuries were reported. The Pennington County Sheriff's office and Rapid City fire and medical teams responded to the accident.