Should be safe enough but the best way to check of course would be to grab fresh plugs after you make the change then once you've got a few hot miles on it then pull them right there on the trail as soon as you stop and see if they are still burning clean. Any chance you've got EGT probes too? That's really helpful for fine tuning.
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I think.... therefore I sled
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Two '94 Indy XLT SKS
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I think.... therefore I sled
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Two '94 Indy XLT SKS