Perhaps you should look at it in another light. Lets say you use a media blaster to clean your plug... you get a little grit in the bottom of the plug, it gets in the engine, and is just accelerated wear and tear. You could heat the plug up with a torch, and burn all the crap out of it, but then again, you compromise the plug in terms of heat cycling. Consider chalking it up to experience. Oftentimes the plugs are just gas fouled and if you let them dry out they will run again. Or you could put them in another machine that took the same plug (my FZR600 took the same plugs, and run them in that to see if they clean up. Usually it will run rough for a few seconds, and then clean up. A lot of work for a few bucks. Figure out why you are fouling, and fix it.
Let me guess, the majority of your fouls are right at the beginning of a ride? If they are, this is a notorious problem. Instead of riding off right after you start your bike, start it, and let it warm up with the choke on, but no load, until the rads are warm to the touch, and the cases are a bit warm. Turn the choke off, and make sure it idles, and is fully warmed up, and ride on.
BTW I used to foul plugs in my WR400 ALL THE TIME until I started warming it up. Have not fouled since (in over 6 months).
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