Why is my battery charge dropping rapidly on my bike?

The ETM RTR Display reads its SOC (State of Charge) based on current battery voltage. Under load there is a phenomenon known as voltage sag that occurs under load. For example, if your battery is fully charged at 67 volts (RTR Lite) or 84 volts (RTR), and you pin it at full throttle, we would generally expect to see voltage sag anywhere from 6-8 volts (which is normal). Once load is removed, voltage will usually return to its resting voltage which is going to be 6-8 volts higher than the voltage under sag.

Because of this, the display errors on the side of caution and will usually display a state of charge lower than what it really is at but it will also reflect the voltage sag and show what appears to show the stage of charge decreasing at an exponential rate. Key cycling the key switch will update the battery voltage reading and you should normally notice an increase in the state of charge.

This is completely normal, and does not mean that your battery is decreasing faster than it has in the past.