MoreBikes has teamed up with OptiMate – the battery saving charger people – to shine some light on the dark art of motorcycle batteries and how to look after them. Find out more at

S is for Short Circuit

A short circuit is an accidental connection between two points in an electric circuit, bypassing the intended circuit. On a motorcycle this can happen when insulation on a wire rubs through on a metal component, allowing the inner wire to ‘connect’ to that part and bypass the rest of the circuit. It can also happen when the ground/earth point is faulty; the flow of electricity will then establish a path of less resistance to follow.


T is for Terminal

All 12V lead-acid batteries have two terminals, one marked ‘+’ positive connected to the ‘cathode’ inside the battery and the other marked ‘-’ negative connected to the ‘anode’. When you ask the battery for power (e.g. turning the starter motor) the sulfate ions inside the electrolyte move from the anode to the cathode, out of the positive terminal and through the starter motor to make it work, then back to the battery again though the negative terminal.

U is for Undone

If you’re working on your bike’s electrical system, make sure you take care when loosening and reconnecting connectors and wiring. A loose or broken cable or connector is a very common cause of electrical faults, and can also drain the battery.


V is for Voltmeter

A voltmeter measures how much voltage is passing between two points in an electrical circuit. It does this by measuring the difference between the positive and the negative input of voltage. It can be used to check the health of your battery: set your voltmeter to the 20 V DC range and connect it to the positive and negative terminals, with ignition OFF. A healthy 12V battery should give a reading between 12.5V–12.8V. Or invest in an OptiMate Testmate, which will do it automatically. To check one out, click HERE.

Ross Mowbray
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