Motorcycle Electric System

Understanding a motorcycle electric system is critical. It helps you discover why something may not be working quite right, without having to strip the bike.

Here is a useful overview that could come in handy when you run into trouble.

Electric System Introduction

As the engine turns the alternator is generating electricity (magnets on copper wires). The electricity generated is powerful (over-powerful) and needs to be regulated by a regulator / justifier. Once corrected the electricity can flow to the component system or the storage system depending on what is need.

Of course a parked bike has no moving fly wheel (electrical generator) and needs the battery to power-up the ignition. After the bike starts moving the junction switch will let the alternator directly power the components (extra current is stored in the battery). If a lot of electricity is needed the battery is asked to provide this.

Now if you have an electrical problem, start by analyzing it in a multiple choice way. The problem you have could be determined by the area (system) which it is in. Think of it as : Lights work (and other components) so charger system might be faulty. Always work with yes / no questions to determine more and more specific where the problem lies.

Watch out when you start messing with the motorcycle electric system (wiring) of the bike. It get’s very very complicated very fast. Wires run through the frame, negative wires are attached to the frame instead of running back to the battery, switches and warning lights are also needed. Be careful, I often analyze it so I can tell the mechanic more specific what problem I am having.

A motorcycle has a small fuse system which avoids components being damaged by a faulty electrical system. The fuses blows instead of the component. Different bikes use different fuses, so check what you need (have a few spares around).

Useful Electric System Tips

  • Motorcycle electric system is split in three different areas: the system which generates electricity, the system which stores the power, the system which directs all the components.
  • Adjusting timing on the ignition is best left to the dealer (and these days it isn’t even regular maintenance anymore)
  • Install sparkplugs with a slightly warm engine, clean around the plug and then pull it out. Insert new plugs smoothly and not too tight.
  • When reinserting a new sparkplug apply some copper grease to help it out the next time.
  • General speaking electrical systems don’t need much attention – it’s the battery that most often needs the maintenance.
  • Remember when adding electrical components (extra lights, GPS, radio) that you need to stay under the total supplied by the charging system, otherwise you end up with problems.
  • Finding problems in an electrical system is hard, it’s nearly impossible without a good electrical system diagram. (check your manual for one)
  • Always remember your electrical circuits need to make full loops. Any damage, break, wrong hookup and electricity will not (can not) flow.
  • Using a test lamp (you know – one of those small lamps is a screwdriver) is one of the most easy and effective ways to check your basic electrics (don’t use it for the high-tech components like onboard pc).
  • Electrical problems fall into three categories short, bad ground or a broken component.
  • Solving a common electric problem – a blown fuse because of a short circuit thru a component, switch, wire e.g. – trace the fuse circuit to help you find the problem
  • Solving a common electric problem – a blown bulb because of wrong usage (touching the glass), old age, vibration or too much voltage.
  • Solving a common electric problem – a slow irregular indicator because of too much resistance in the electricity flow – check the circuits and components.
  • Solving a common electric problem – weak lights (which get stronger as you power the engine) because of bad grounding between light and frame


Simply the most effective way to find motorcycle electric parts. The parts wizard guides you through 7 MILLION PARTS to arrive at exactly the right item you need. Quickest Way to the Right Motorcycle Electric Parts …

Leave a Comment

Your email address will not be published. Required fields are marked *