From a press release issued by Castrol North America and obviously written before Chuck Sorensen won his third AMA 250cc Grand Prix Championship at VIR:

“Currently racing in the hot number one seat of the AMA 250 Grand Prix, rider Chuck Sorensen is tearing up the tracks with help from Castrol. Castrol Motorcycle supports a number of teams in the motorcycle circuit including the Castrol Honda World Superbike Team with rider Colin Edwards, the 2002 Laguna Seca winner. Castrol also sponsors the Castrol Ducati Pro Thunder team with rider Kurt Marmor.

“Castrol looks to support enthusiastic, young riders who are racing ambitiously within the competitive circuits,” says Andrew Della Bella, Trade Marketing Manager for Castrol Motorcycle. Chuck Sorensen has been a competitive rider since 1990….Using Castrol 747 Premix for his Stargel Aprilia RSV250 engine and Castrol SRF Racing Brake Fluid for his brakes, Sorensen is sure to be tough competition for his fellow riders.”