Motorcycle Battery Voltage Range

Fully charged our redtops including 34m bluetop will read approximately 12 6 12 8 volts and our yellowtops will read approximately 13 0 13 2 volts including bluetops with light gray cases.

Motorcycle battery voltage range.

Place the voltmeter leads to the battery terminals. 12 volt motorcycle batteries supply useful energy only through a limited voltaic range from over 14 volts when fully charged and rested down to 10 5 volts in use under load this battery is noticed when lights dim or your motorcycle is hard to start. Likewise a 12v battery is made up of six individual cells giving a total of 6 x 2 1v 12 6 volts. We call this the open cell.

If the battery begins to hold and then steadily drops in voltage there is a problem. If it reads below those values then your battery is not keeping a full charge. No 12 volt battery will remain at over 14 volts for more than seconds unless it s being charged. Even though you are testing a 12 volt battery you should know that a battery that is truly 12 0 volts is a boat anchor.

When any 12 volt battery is discharged below 12 4 volts sulfation begins to occur within the battery. Here is a quick breakdown on the spectrum of voltage ranges. A good battery should read between 12 4 to 12 6 volts 12 6v being optimal. The following table shows how battery voltage corresponds with state of charge at 80 degrees f.

A fully charged 12 volt motorcycle battery should measure about 12 6 13 5 volts between terminals depending upon its chemistry. A battery is at a discharge anywhere from 11 9 to way below that range. A healthy 12 volt motorcycle battery should maintain a range from 9 5 10 5 volts under the load for a good 30 seconds straight. 12 volt batteries supply useful energy only through a limited range from over 14 volts when fully charged and unrested down to 10 5 volts in use under load when lights dim your motorcycle is hard to start.

If the voltage instantly drops to 0 volts that is also a problem. The full range of the battery is from just over 14 volts when being charged by the bike running at high rpms down to 10 5 volts under heavy load for example when the lights are on and the bike is being started. Positive to positive and negative to negative.