It may not be the plugs fault, but the plug may be one reason for the seizure. If you are reading the wrong portion of the plug insulator during plug chops(plug TIP, as opposed to inner insulator BASE) the cooler plug will give you a false darker reading that "looks" like the bike is jetted correctly when in fact it is running LEAN. In order to properly check your plug, you either need to run the plug down on a lathe to see this portion, or get one of those handy plug magnifier/illuminator tools.
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Paul Herr
'88 FZR4/GSXR/YZF Frankenbike
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