How to Change the Spark Plugs on Your Motorcycle
Making sure your spark plugs are in working order is one part of motorcycle maintenance. Matt Bochnak from HowToMotorcycleRepair.com demonstrates how to change your own motorcycle spark plugs in the video below.
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– [MATT] Hey, what’s up everyone, it’s Matt from HowToMotorcycleRepair.com. In this video, I’m going to show you how to change the spark plugs on your motorcycle.
Changing the spark plugs on your motorcycle can be an easy DIY job that can take as little as 30 minutes, depending on the model that you have.
A spark plug creates a spark, which ignites the fuel/air mixture inside the combustion chamber. Replacing your spark plugs may help improve the running condition of your motorcycle engine, since spark plugs do wear out over time.
It is always a good idea to plan ahead and look up the spark plug part number required for your model in the owner’s or service manual. These manuals will also include information on how often the plugs should be changed. Once you find the part number, you can buy the spark plugs from your motorcycle dealer, or order them from an auto parts store.
As far as tools, you will need a ratchet, some extensions, a spark plug socket and a plug gap gauge. A spark plug socket has a rubber insert that helps hold the spark plug in place. A spark plug will fall out of a regular socket, which can be a little more difficult to work with.
Before you remove a spark plug, make sure the ignition key is in the off position and the engine is cool. Then, remove the spark plug cap by pulling on it. Do not pull on the wire lead. Put the spark plug socket and any extensions that may be needed in place. Then, use the ratchet to loosen and remove the spark plug.
Before installing a new spark plug, it is a good idea to check the plug gap. The gap refers to the distance between the side electrode and center electrode. The plug gap specification will be outlined in the service manual. Most likely the plug will come pre-gapped from the manufacturer — however, it is always good practice to double check. The gap is measured by using a plug gap gauge. The gauge is inserted into the gap, and then rotated until all slack is removed. The side electrode is used as a pointer to read the gauge markings. As you can see, this plug gap is twenty-eight thousands of an inch.
If you need to close the plug gap, simply tap the spark plug on your workbench with the side electrode facing down. Repeat until the desired plug gap is achieved.
To open the plug gap, use a plug gapping tool to bend the side electrode. Repeat until the desired plug gap is achieved.
Install the spark plug using the socket and extension, and turn it slowly by hand. This is to prevent cross threading. Cross threading occurs if the spark plug is installed at an angle, and it can damage the threads in the cylinder head. If it becomes difficult to turn, stop, remove the plug, and try again. Once the spark plug is threaded in all the way by hand, and the gasket touches the cylinder head, use a ratchet and tighten it up. Make sure to tighten about one-half to two-thirds of a turn to compress the new sealing washer on the spark plug. The sealing gasket comes preinstalled on the spark plug. Here is a brand new plug next to an old plug, and you can see how the gasket compresses during installation.
Now, you can reinstall the spark plug cap. When pushing the cap back on, listen carefully for a “snap” sound and feel. This will indicate that the cap is installed properly.
Repeat this process for each cylinder of your engine. This model is a four cylinder and has four spark plugs.
OK, this job is complete, however, if you are trying to diagnose a nonrunning motorcycle and suspect it has ignition issues, go ahead and click on the link in the upper right, and watch a video on how to check three simple things to help diagnose a nonrunning engine. It shows how to check for spark on a motorcycle.
(icard link: https://youtu.be/l0g7S3BYcFg)
Alright, I hope you enjoyed this video on how to replace spark plugs on your motorcycle.
If you’d like to see more of my videos, head over to HowToMotorcycleRepair.com, or check out my YouTube channel, MatthewMCrepair. I’m also on Facebook and Twitter. Thanks for watching and see you next time.
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