The Kawasaki FH580V-(G)S20-S KAI is a 0.59 l (585 cc, 35.7 cu-in) V-twin 90Ā° air-cooled 4-stroke internal combustion small gasoline engine with vertical shaft. The Kaiās are the newer series engine. The Japanese word āKAIā means evolution, advancement and renewal. The FH580V KAI engine is based on the FH580V motor, but it uses redesigned air cleaner and blower housings, new air filter options, internally vented carburetor, an advanced lubrication system design, and enhancements for optimal stability.