i have a 2003 manual 400 with 500 miles should i change the plug. thanks

 

yes, every two years at a minimum

 

Mountainclimber,

I own a 2003 400 as well. I have been changing the spark plug and checking valve clearence every 12 months. I have about 4000 miles in it.

You have to remove the fuel tank to check the valve clearence and it gives easy access to the spark plug too. But, It is not necessary to remove the fuel tank to change the spark plug.

I know some who run a hotter plug in winter and the regular plug in summer.

Hope this helps

SJ

 

Spark plugs are cheap, so buy and install the cheap insurance and change that plug every spring.