Quote from Yamaha Tech Exchange:
"The YFZ450 Charging System is designed to supply at low to medium engine rpm a maximum charging rate with the headlights in the ON position. Under some conditions (e.g., low speed with cooling fan running requently or continuous high rpm riding), it may be necessary to ride with the headlights in the ON position continuously to maintain a fully charged battery."
"Symptom: ...the YFZ450 Charging System is designed to supply at low to medium engine rpm a maximum charging rate with the headlights switched to the ON position. If the headlights are removed for competition use, the unit may experience battery discharging."
"Remedy: Install the YFZ450 Resistor Kit. The kit contains a ceramic resistor which takes the place of the headlights to maximize the charging rate, plus it provides a higher temperature fan thermoswitch to minimize current draw. NOTE: This higher temperature is still low enough to not cause engine overheating. The kit is optional for competition use and warranty does not apply. The kit was developed to allow maximum charging and reduce battery load.
See the YFZ450 Accessory page to purchase the kit.
