On the engine of the 1998 Honda CR 250 is one spark plug on the top of the piston sleeve (top end). This is a basic job that must be done correctly to ensure that you are getting the most power from the engine while riding. The recommended spark plug is an NGK high temp. If the new spark plug is installed incorrectly, then the engine will cut out and foul the new plug.
Step One: Setting up the engine
Support the CR 250 using the rear axle stand. Allow the engine to cool and then remove the rubber wire on the top of the stock spark plug. Spray brake cleaner onto the top of the piston sleeve and then wipe off debris to ensure that no debris fall into the top end once the spark plug has been removed.
Tip: Brake cleaner will evaporate and is the safest thing to use around this component.
Step Two: Removing the spark plug
Using a 1 inch adjustable wrench, turn the stock spark plug counter clockwise until the plug releases from the top end. Pull the stock spark plug from the top end and then discard it.
Tip: This is going to be a tight fit. You may have to try and grab onto the stock plug with the wrench a few times before it is securely tightened onto the plug.
Step Three: Gapping the new plug
Hold the new spark plug in one hand and the spark plug gapping tool in the other. Place the thin metal edge of the spark plug gapper under the metal arm on the top of the new spark plug. Turn the spark plug gapper until the numbers 0.032 are in the center of the metal arm on the new spark plug. Remove the spark plug gapper from the new spark plug.
Step Four: Installing the new plug
Insert the new spark plug into the top end of the engine so that the white end of the new plug is sticking out on the top end in clear view. Tighten the new spark plug until it is tightly snug. Place the rubber wire onto the tip of the new plug and push down on it until you hear a click.
Step Five: Starting the engine
Start the engine and rev the engine three to five times to ensure that the new plug is installed and working correctly. Turn the engine off.
You can but the wrench and a box of new spark plug from the Honda dealer or any auto parts store. Changing the spark plug can be done just about anywhere as long as you have the tools.
Robert Good - Robert is an avid traveler and spends much of his time on the road looking for new things to write about.
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