Apico Radiator Cap . This is a perfect upgrade for most motocross radiators with standard caps.
 
HONDA CR125 04-07 CR250 04-07 CRF250R 04-16 CRF250X 04-16 CRF450R 04-16 CRF450X 05-16 YAMAHA YZ125 YZ250 YZ250F YZ450F