CRF Spark Plugs

[wardd]

2004 CRF450 owner here.

I'm looking to pick up a spare plug for those far away racing trips.
According to Servicehonda.com, there are two possible plug applications (both NGK) for 2002-2004 CRF450, 'IFR9H11' or 'IFR8H11'. The cost of both seems to be the same.

I've not had an occassion to pull mine out yet(and I hope I don't....), so I'm not sure which I'm running. Does anyone know the difference? I'm guessing one of them runs hotter.

Also, it appears one would need to remove the tank to get at the plug on the CRF. Is this correct, or does someone have another method? Certainly not a big deal, just an observation from a newbie thumper owner.

Thanks....
David.

 

[Casper250]

I believe one of the plugs is stock on the 250 and the other is stock on the 450 but don't hold me to that. I remeber getting some plugs at the dealer and he said something to that account. If I remember, i'll take a look at the plug number tonight on my 250 and let you know. As for the tank, you do need to remove it to get to the plug.

 

[xr284]

I have the IFR811H in my 03 crf 450, i am not positvive but i bet you have the IFR911H in your 2004, because of the higher compression ratio.Its a hotter plug. You do have to take off the gas tank but it dosent take that long, just remember to remove the bottom bolts on the shrouds only, so that way when you pull the tank the shrouds come with it. Make sure you have the honda spark plug tool because it is a huge pain without it.

 

[Rich Rohrich]

The 'IFR8H11' is the standard plug for the CRF450. If you are running WOT for extended periods of time with a modified engine the 'IFR9H11' is an optional cooler plug. Most people will never have a need for the cooler 'IFR9H11' plug.