2000 Yamaha YFM400FWA(M) Factory Service workshop Manual, Page 111Get this manual
BATTERY INSPECTION
INSP ADJ
Batteries generate explosive hydrogen gasAlways follow these preventive measures: Charge batteries in well-ventilated areaKeep batteries away from fire, sparks or open flames (e.g welding equipment, lighted cigarettes, etcDO NOT SMOKE when charging or handling batteriesKEEP BATTERIES AND ELECTROLYTE OUT OF REACH OF CHILDREN1.Remove: Seat Battery holding bracket Battery lead cover Refer to "SEAT, CARRIERS, FENDERS AND FUEL TANK"
2.Disconnect: Battery leads