2005 Ski-Doo RT Series Shop Manual, Page 182Get this manual
Section 05 ELECTRICAL SYSTEM Subsection 02 (CHARGING SYSTEM)
Battery Charging WARNING
Always wear safety glasses and charge in ventilated areaNever charge or boost battery while installed on vehicleDo not open the sealed caps during chargingDo not place battery near open flameCAUTION: If battery becomes hot, stop charging and allow it to cool before continuingNOTE: Sealed VRLA batteries have an internal safety valveIf battery pressure increases due to overcharging, the valve opens to release excess pressure, preventing battery damagePerform BATTERY CHARGE TESTING above then proceed as described hereAn automatic charger is the fastest and most convenient way for error-proof chargingWhen using constant current charger, charge battery according to the chart belowBattery Voltage Below 12.8 and Above 11.5 V
STANDARD CHARGING (RECOMMENDED) BATTERY TYPE YTX20L-BS TIME 49 hours QUICK CHARGING BATTERY TYPE YTX20L-BS TIME 50 minutes CHARGE 10 CHARGE A
If the charger ammeter shows no change in current after minutes, you need new batteryCurrent flowing into the battery at high voltage can become excessiveMonitor amperage and adjust voltage as necessary to keep current at the battery's standard amp ratingCharge for approximately 20 hours