A motorcycle rider who crashed Sunday during a ride east of Healdsburg may have suffered a medical condition prior to losing control of his bike, the CHP said Monday.

Frederick Dunlap, 67, of Graton was approaching a turn on Highway 128 east of Chalk Hill Road when he rode off the roadway, said CHP Officer Kerri Post.

Dunlap reportedly had been traveling with several other motorcycle riders at the time of the 12:50 p.m. crash.

After he went down, he was unresponsive and began turning blue, according to the CHP. An emergency room nurse stopped to help, performed CPR and provided aid until paramedics arrived.

He regained consciousness and was flown to Santa Rosa Memorial Hospital. He was listed in critical condition late Monday.

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