The motorcyclist involved in a Portland collision early Thursday remains in serious condition at Maine Medical Center.

James Bragg, 27, of Independence Drive in Freeport was driving a 2002 Harley Davidson east on Grant Street at 12:45 a.m. when he apparently failed to stop for a stop sign and crashed into a 2000 Chevrolet 1500 pickup headed south on State Street. The motorcycle hit the passenger side of the pickup truck and Bragg ended up under the truck.

Bragg was not wearing a helmet, police said.

Police say there was no indication at the scene that alcohol was involved and say that excessive speed is the primary cause of the crash. The speed limit on Grant Street is 25 mph, as it is on all downtown streets not posted otherwise.

The driver of the pickup, Naomi Stewlow, 23 of Sebago, and her passenger Dax Frank, 39 of Harrison, were not badly hurt but were transported to Maine Medical Center as a precaution and later released, police said.

Police are still investigating the crash and say they have not been able to interview Bragg yet because he remains unconscious.

Police asked that anyone who witnessed the crash call the Portland Police Traffic Division at 874-8532.