PLEASANTON--Pleasanton police are asking for the public's help in locating a driver who struck a motorcyclist on Tuesday, causing significant injuries.

The victim, a 45-year-old man, was riding on Stoneridge Drive near Rialto Way when he was struck by a pickup truck at 5 p.m. He was transported to Eden Hospital with significant injuries, but is expected to survive.

Multiple witnesses told police described the vehicle that struck the cyclist as a black Toyota Tacoma or "Nissan-type" pickup truck. The truck has chrome rims and may have its rear window tinted and a fiberglass bed cover. Witnesses described the suspect as being in his mid- to late thirties with black hair.

Anyone with information about the accident is asked to call the Pleasanton Police Department at 925-931-5100.

Contact Karina Ioffee at 650-576-9626. Follow her at Twitter.com/kioffee.