Castrol Power 1 4T 15W-50 is designed to manage heat & friction to provide sustained power delivery and on-demand acceleration. It is suitable for all 4-stroke motorcycle engines, both carburetor and fuel injected where API SN (or below) and JASO MA or MA2 are recommended. Castrol POWER1 4T with Power Sustain Technology™ is designed specifically for bikers who love the exhilaration of riding. New Castrol POWER1 4T with Power Sustain Technology™ manages heat and friction, ensuring continuous power delivery and provides on-demand acceleration.