Is A Motorcycle Battery AC Or DC?

Motorcycle Battery AC or DC

Early in my beginner riding days, I always wondered whether the motorcycle battery is AC or DC.

Is A Motorcycle Battery AC Or DC? All motorcycle batteries are DC batteries. The electrical accessories and systems in motorcycles need DC which is powered by the battery. As a result, motorcycle batteries operate on DC, or direct current.

Let’s deep dive into the specifics of a motorcycle battery, shall we?

Are Motorcycle Batteries AC or DC

Invariably, all motorcycle batteries operate on DC, or direct current.

The electrical accessories and electric systems in a motorcycle require to DC to power them up. And since battery is their source of power, the battery is required to be a DC battery.

Although the alternator generates AC, or alternating current in the motorcycle, the regulator-rectifier converts this AC into DC so that the charge can be stored in the battery.

All motorcycle batteries are DC operated batteries.

These batteries operate on direct current, receiving the charge from alternator and regulator and using the charge to powering the electrical systems.

The alternator in the motorcycle generates AC, or alternating current by converting the mechanical energy derived from the engine.

This AC, or alternating current cannot be used since the battery operates on DC, or direct current.

There is a regulator-rectifier circuit present in the motorcycle which bridges this gap. The regulator-rectifier will convert the AC (alternating current) from the alternator into DC (direct current) so that the battery can store the charge.

So, in short, motorcycle batteries operate on DC, or direct current as the electrical systems in the motorcycle can be powered only through DC (direct current).

And that’s why, motorcycle batteries are invariably made to be DC batteries.

Charging System – Alternator, Regulator, And Battery

The battery along with the alternator and the regulator/rectifier forms the charging system in a motorcycle.

Alternator: The alternator in a motorcycle converts the mechanical energy – which is derived from the crankshaft through the engine – into electrical energy in the form of alternating current, or AC.

Regulator – Rectifier: The regulator combined with rectifier converts the alternating current (AC) generated in the alternator into direct current (DC). Since battery is DC, the AC coming from the alternator has to converted into DC.

Battery: The battery acts as the power source in a motorcycle. It provides direct current (DC) to the ignition system as well as supplies current to the accessories in the bike above the alternator output whenever required.

Together with the alternator and regulator-rectifier, the battery supplies DC, or direct current to power all the electric accessories and electrical systems in the motorcycle.

Motorcycle Battery Voltage

Almost invariably, all modern motorcycles have 12 Volt batteries.

Although the battery capacities – the amp-hour rating of the battery will vary across motorcycle manufacturers and the models, the voltage specification will be the same at 12 Volts.

6 Volt batteries are a thing of past. The modern electrical accessories and the circuits operate on 12 Volt batteries in the motorcycles.

You can find 6 Volt batteries only in old vintage motorcycles and dirt bikes.

How Long Does It Take To Charge A Motorcycle Battery?

Typically, a 12V motorcycle battery can take anywhere between 4 hours to 24 hours to get charged completely.

The charging time entirely depends on:

  • The type of battery
  • Charger type
  • Battery specifications (capacity, voltage etc.)
  • Battery age and condition

For a detailed description, check out our post on battery charging time.

While lead acid battery, AGM battery and Lithium-ion battery can charge quickly, gel batteries take much more time to charge.

A trickle charger will take much more time to charge whereas a float or a smart charger will charge the battery much more quickly.

Related Questions

Can your motorcycle run without a battery?

Most modern motorcycles cannot run without a battery. If the battery is at marginal health and some life still left in it, motorcycle can be started with a push/bump start.

The only exception where battery is not needed to run are motorcycles with magneto ignition, which can be seen in old motorcycles, small dirt bikes and scooters.

Will a motorcycle battery recharge itself?

Battery gets recharged in the motorcycle by deriving power from the engine. The alternator in conjunction with regulator supplies DC to the battery.

The battery recharge depends on the power requirements of the accessories in the bike and the alternator output derived from the engine.

What are the reasons for a dead battery in a motorcycle?

The main reasons for a dead battery in a motorcycle are:

  • Poor Voltage Regulator
  • Corrosion of battery terminals
  • Bad ground connection
  • Short in the electric circuit
  • Excess heat and vibration

For preventive maintenance of the motorcycle battery, you need to – clean the outer layer and terminals of the battery regularly, check electrolyte levels if the battery is not maintenance free and tighten the battery caps frequently.