Tachometers are important tools for any motorcycle owner because they give you a better understanding of the speed of your engine. They can help you find and correct engine speed issues and maintain optimal fuel economy. In addition, tachometers can be used to help with troubleshooting and preventative maintenance.
How to Connect a Tachometer
The process of connecting a tachometer in your motorcycle is fairly simple and can be completed with minimal knowledge of electrical wiring. It is best to take it on a test ride afterward to ensure that it is working properly and to verify that your tachometer is operating correctly at all engine speeds.
First, remove the fuel tank and all other hoses and connectors from your motorcycle. This is a time-consuming process, but siphoning out the fuel beforehand will make it easier to lift the tank.
Next, find the appropriate tach wire on your bike and cut it to a length that will allow you to run it back into the headlight housing (sheathed in shrink tubing will make it look neater) and then up along the left side of the motorcycle to where the ignition coil is located. Trim any excess wire covering until only a few inches remain inside the housing and then attach it to the tachometer’s wiring with an automotive wire connector, such as the ones sold at most auto supply stores.
Once you’ve run the tach wire up to where the coil is, use a multimeter or a test light to locate the tachometer’s signal and ground wires. Depending on the make and model of your motorcycle, the signals may be different colors, so you should refer to the manual that came with your tachometer for guidance.
Using the multimeter, check the resistance of each connection between the tachometer’s signal and the tachometer’s ground wires. Ideally, the resistance should be between 1.0 and 1.5 volts. If it’s not, you might have a loose connection or the tachometer isn’t receiving enough power from the ignition.
When you have finished, reconnect the tachometer’s power wires to the positive wire in the headlight bucket and verify that the tachometer is receiving enough power. If it isn’t, repeat the connection process until you have successfully connected all of the tachometer’s wires to the positive and negative wires in the headlight bucket.
If you have an aftermarket tachometer, you will need to change the connector from a female flat crimp type to a male multistack connector that is designed for a tachometer. You can find these at most VW dealerships or sand buggy outlets.
You’ll need a pair of insulated tools to work on your tachometer. The most common is a needle nose pliers, but you can also use a pair of screwdrivers to get to the wires.
Tachometers are made by a variety of manufacturers, so it is important to choose one that works with your particular motorcycle. It is also important to make sure that the tachometer is compatible with your vehicle’s electrical system. If you’re not sure which tachometer to purchase, look for ones that have a good reputation for quality and reliability.