Any real advantage of Iridium plugs in motorcycle?
- Thread starter ZZman
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My CRF450 had factory iridium plugs.
I would say high rpm bikes would benefit.
Iridium and platinum require less voltage to fire, at high RPM this may make a difference in reducing the possibility of a misfire.
Some bikes fire the plugs on every stroke (wasted spark) plugs wear out twice as fast. Iridiums in the Wife's Nija 250
Are holding up well.
Good point, many bikes use waste spark ignition (2 plug wires per coil) and double precious metal plugs will last much longer.
Sure they do. Iridium are usually fine wire plugs. With small electrode area at the tip they concentrate the ionization charge and make it easier to fire. So you can usually open them up at least 0.005 over standard plugs w/o adding any load to the coils. Bigger spark gap is better ignition when it goes off 
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Even some autos are now using wasted spark ignitions.
Iridium plugs will last a lot longer in cycles just like
in cars and trucks.
Honda originally called for plug changes at 8000 miles=
ridiculous.
Originally Posted By: dwendt44
Even some autos are now using wasted spark ignitions.
Originally Posted By: ZZman
Iridium plugs can make sense in a car with hard to reach plugs and rack up lots of miles. But do they really make sense in a motorcycle that gets a few thousand miles a year and aren't hard to change?
I can change the plug on my 150 in a minute .. it's FUN.
My 650 savage requires seat/tank removal plus other work to get to the plug ... NOT FUN.
150 gets cheap plug - 650 gets Iridium 
My 2013 Honda pickup came from the factory with double-iridium plugs, and they specify them for replacement _just_ after the emissions performance requirement ends.
My 2012 Honda motorcycle came from the factory with double-iridium plugs, and they specify them for replacement _just_ after the emissions performance requirement ends.
Perhaps this is _only_ coincidence?
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