WR426F Fouling Plugs

Hi guys,

My buddy has a 02WR426f that fouls plugs everytime he takes his bike for a ride, the rings are fine, but he is having to change the plug every time he goes riding, If the bike does not start the first three or four kicks, the plug is fouled, and he has to replace, any advice or input will be appreciated.

Thank you!

What all do you know about how the bike is jetted/idle screw setting/needle setting? Does your buddy know not to give it any throttle when starting it? How does the bike run once he gets it started?

As mentioned above, I'd go down the fuel side of things first. If that fails though, might pay to check your electrics.

I had a similar problem with a WR426 a couple of years ago. Turned out, my secondary coil wasn't putting enough spark out.

So when I did the usual check to see if I was getting spark it would come up positive, yet would foul plugs and break up when I hit the mid-range or above.

When it is running, does it perform okay?

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