How to Tune a Yamaha YZ250

The Yamaha YZ250 is an off-road motorcycle that was initially introduced by Yamaha in the 1970s. Since that time, it has become popular with motorcyclists. Tuning up your Yamaha YZ250 is a regular part of maintenance right along with regular oil changes. Purchase replacement spark plugs at your local Yamaha dealership to ensure you get the right plugs for your bike. It will take you approximately 30 minutes to gap your new plug and install it.

Things You'll Need

  • Pliers
  • Spark plug wrench
  • Spark plug gauge
  • Remove your new spark plug from its package. Gently pry open the wire on top of the spark plug. Set the spark plug gauge's gap at exactly .050 inches. This is the correct gap size for your Yamaha YZ250's plug.

  • Set the tip of the spark plug gauge inside the wire and then squeeze it closed. This will set your new plug's gap accordingly. One you have gapped your new plug, set it on the side.

  • Remove the spark plug wire from your old plug and inspect if for any damages.

  • Use your spark plug wrench to remove the old plug. Turn the wrench counterclockwise to loosen and remove the plug.

  • Sit the end of the new plug in the spark plug hole and turn it clockwise by hand. Tighten it with your plug wrench. Replace the spark plug wire once the new plug is completely installed.