1997 Yamaha YFM600FWAK ATV Service Manual, Page 104Get this manual
IIANOSJP Ito) -BATTERY INSPECTION Charging method using constant-voltage type charger
Measure the open-ci rcuit voltage prior to charging
Voltage should be measured 30 minutes after the machine is stopped
Connect charger and AMP meter to the battery and start charging
Make sure the current is higher than the standard charging current written on the battery