How to Change Motorcycle Spark Plugs

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Spark plugs play an integral part of a motorcycle’s performance. Spark plugs can also go bad for many reasons and are designed to be repaired.

It is easy to replace spark plugs, but it takes patience and the right tools. If you suspect your motorcycle’s engine needs a tune up, you may be wondering how to change old spark plugs.

How to change the spark plugs on a motorcycle

  • Purchase new spark plugs as specified by the manufacturer
  • The spark plug wires should be removed
  • Use socket wrench to remove old spark plug
  • Check the condition of your old spark plug
  • Hand-install a new spark plug
  • Torque spark plug and socket wrench
  • Install spark plug wire

Your motorcycle’s performance can be affected if your spark plugs are not replaced on time. This article will teach how to do it correctly and on time so you don’t cause any unnecessary damage to your engine.

Procedure to Replace Motorcycle Spark Plugs

Here’s how to replace your spark plugs on your motorcycle.

  1. Make sure to have the correct sparkplugs The correct type can be found in your owners manual. If that’s not an option, parts stores or motorcycle shops can help look it up or match a new plug with your old one.
  2. Make sure you have the right tools. The right size spark plug socket is essential for this task. It will save you a lot of time, effort, and headaches. These sockets come with a rubber grommet to grip the plug. You can find them at parts stores, hardware shops, and online. You will need the tools to remove the plugs from some engines that have them hidden under the tank or covers.
  3. Locate the sparkplugs and take out the wires. The number of spark plugs on a motorcycle will vary depending on its engine type. Pull the wires out of the spark plug by pulling hard.
  4. With a socket wrench or your spark plug socket, turn the sparkplug counterclockwise. To reduce the risk of burns, it is best to do this while your engine is still cold. It is also difficult to remove plugs if warm metal expands.
  5. After the spark plug is removed, examine the condition. This can reveal a lot about the engine’s performance. Below are more details about spark plug condition.
  6. Make sure to check the gap between the old and new spark plugs. Good sparks require a gap. For more information, refer to your owner’s manual. However, most spark plugs are pre-gapped. There are many gapping tools that can be used to adjust the spark plugs at parts shops.
  7. You can install the spark plug manually. Installing it by hand ensures it won’t cross-thread. Also, install the plug dry–meaning no anti-seize–as this can cause over-tightening.
  8. Once the washer on the plug is seated to the engine, give it ¼-½ a turn clockwise with your socket wrench. It is important to not tighten the plug too much as it can easily damage or strip the threads.

If necessary, repeat the process for all spark plugs. Start the engine to make sure everything is running smoothly.

What is it? “Spark Plug Gap” What can I do to verify it?

As we mentioned earlier, the gap in your spark plugs is the space between the pointed electrode tip (the curved tip) and the pointed metal tip (the metal tip).. This is where the voltage charge jumps over, which ignites air/fuel mixture. It’s similar to how lightning jumps from the clouds to the earth.

So what is the significance of spark plug gap? If the gap is too small, there won’t be a big enough spark to generate the required heat to ignite your air/fuel mixture. Too much gap can cause the voltage to have trouble arcing. As fuel is not burned, both conditions will cause poor performance.

To check the gap between spark plugs, use a professional gapping tool. It has built-in gauges that you can insert between the electrodes.. Refer to your owner’s manual for specifications for your particular engine. To adjust the electrode, don’t use a screwdriver. This can cause damage to your plug. An excellent spark plug gapping tool will include a keyway that can be used to bend the electrode to the correct gap.

What is the best time to change my spark plugs?

You might be left wondering what you can do after reading all of this. “When should I change my spark plugs?” There are several options depending on your specific situation.

Spark plugs are subject to a service life. This is part of regular maintenance and upkeep. Whenever possible, refer to the manufacturer’s manual for your specific engine for what your engine needs. Typically, spark plugs should last a long time–around 15,000 miles–but are subject to your riding style.

An off-road bike may take more abuse than a street bicycle and may need to be serviced sooner.. If you only ride seasonally, you may never need to change the plugs because they just won’t be used enough to wear out.

You should inspect your plugs as part of a preventative maintenance program. The possibility exists that the threads of your plug could seize in your engine cylinder heads. This would require you to rebuild or replace your engine cylinder. Regular inspection of your spark plugs will reduce the likelihood of them seizing in your head. It also allows you to get a better idea about the engine’s performance.

What can I learn about my spark plugs?

Now that you have your new spark plugs in, it’s time to look at the old ones. The condition of your spark plugs can tell you a lot about how efficient your engine is and what potential problems it may have.

A spark plug that has a thin layer tan coloring is a good indication of a running engine.. It could indicate a high level of carbon buildup. This could be caused by a badly tuned carburetor, poor spark, or a dirty air filter.

If oil is visible on spark plugs it means that there is an oil leak inside. This should be dealt with immediately. Also, a bent or broken spark plug indicates that either the spark plug was not installed correctly or that there has been a mechanical fault. These conditions must be rectified immediately.

Carbon tracking, another issue that spark plugs could have, is also a possibility. This occurs when the spark plug’s ceramic insulator cracks. It allows some of the buildup electrical charge to escape and deposits carbon along the cracks.

The insulating part of the plug can be inspected for thin black or brown streaks. They should be replaced because they can cause weak ignition and poor performance.

Why are there so many types of spark plugs? Which should I use?

There are many spark plug manufacturers and it can be confusing to choose which one to purchase. As mentioned, the owners manual is the best source of information on what spark plugs to buy.

It is difficult to argue about the quality differences between brands. Everyone seems to have a favorite brand. If you aren’t worried about being brand loyal, it’s not going to matter too much which brand you go with. There are however a few things you should consider.

Check that the pitch and thread diameter are correct for your engine. The diameter refers the size of the threaded area of the plug. The thread pitch is the degree of coarseness or fineness of the threads. You can measure the diameter with calipers, and the pitch using a gauge. This can be useful if you don’t have a technical resource, like a manual, to refer to.

Make sure to only buy parts from reputable sources. Although it may seem like a great idea, buying cheap parts online can lead to more problems due the poor quality. The cost of good plugs is generally low, so it’s not a reason to purchase the most expensive ones online.

How to Keep Spark Plugs in Good Condition

  • It is important to use the correct plug for each engine.
  • Be aware of any misfiring, loss of power or sputtering coming from your engine. This could indicate that the plug needs to be replaced.
  • Regularly inspect your motorcycle and check the condition of your sparkplugs.
  • Always have a spare plug and the necessary tools handy just in case.
  • Don’t be intimidated by the task of replacing spark plugs. You don’t need to be intimidated by the task of replacing spark plugs. This is a simple project that will improve your motorcycle’s performance and longevity.

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