Spark plug changes

[Blinx]

I recently did my 4000 mile service for my FMX and went through everything. The spark plug had only done 3500 miles and was already rusted completely! The spark on it was very inconsistant to so I replaced it.

I was wondering, obviously my restrictor will cause the bike to run slightly leaner than most, explaining why the plug got shagged so quickly, but when I spoke to Honda they said part of their restriction kit included a spark inhibitor for the CDI. Any idea what this does?? Im getting to the point of ripping my restricting washer out. Its not doing the engine any good at all I dont think.

Also does anyone else have problems with spark plugs getting badly corroded around the outside/burnt out quickly? How often do you guys replace yours?

[switch]

Corroded? Good GOD, that thing should NEVER be corroded. White-out, perhaps?

[Blinx]

The hex head part of the spark plug was badly corroded as well as the washer, but I think its because its at the front of the engine and probably gets alot of water kicked at it when I ride in the wet. The actual contacts didn't look too bad. No fouling and not to white either.

Spark was quite weak and jumped all over but much better on the new one.

[Rubberchicken]

They rust like hell on the bit not covered by the cap outside of the engine, but like switch said the bit that actually sparks should never ever be rusty. A bit white around the nose perhaps...

I'd fitted a Platinum plug to my NX that's lasted for 18000 miles (though admittedly it was well shagged near the end) now replaced by an Iridium one that I expect to last about as long.

The restrictor kit won't help you any indeed, it's goal is opposite to having the engine run well, so it'll probably run lean and you probably can't do much about that.

But.

DON'T just rip the plate out.

I'm not completely aware of the rules surrounding the British licence, but I imagine it won't be that much different from the ones here in NL.

That plate is there for a reason, a legal reason. Riding a full power bike on a limited licence won't be legal, and insurance companies just love an excuse to not have to pay anything.

Imagine if you will the scenario where you cause an accident and cripple somebody, and the insurance company basically says get lost kid, you broke the terms of your insurance, you get to sort out the mess. Which they will.

I can recommend the Iridium plug (the NX uses NGK-DPR8EIX9) because it gives a sharper spark, the bike seems to start easier and the plug lasts longer than the regular ones. Should be 7 quid or so on ebay, I got mine from ebay.co.uk anyway.

[Blinx]

Ah yea I think thats what I have replaced it with actually. It definitly had a much sharper spark. I havn't had time to reassemble bike yet so I'll be intrigued to see how much it improves starting, especially in the cold!

Yeah, I think it's only another year to bear with it. It just seems an ilogical way of restricting the bike without readjusting the mixture and fuel etc. I think throttle stops like they have on some bikes seems like a much better idea.

[switch]

Starting in cold IS a bit easier, since Iridium plugs don't suffer from a certain 'oeprating temperature' range. Cold weather plugs start easier while warm weather plugs start not as fine on a cold engine.

If the plug's rusty on the outside, the covering cap (red-orange rubbery thing) might not be as insulating to the elements as it should. Have you ever had your engine cut-out in moist / wet weather?