2008 YZ450F upgrade to NGK Iridium Plug

I just bought 4 iridium plugs for my 08 YZ450f and they are not the right size. The dealer told me they were. The stock plug is a NGK CR8E. I need to get iridium plug that replaces these plugs. Does anyone know? Thanks:confused:

Oh yeah the plug that they gave me was a CR8HIX. (Stock#7669) The electrode is about 1/4 inch too short. The overall plug is roughly 3/8Inch shorter.

I think it is a CR8EIX but on the application chart it only goes to 2005

I just bought 4 iridium plugs for my 08 YZ450f and they are not the right size. The dealer told me they were. The stock plug is a NGK CR8E. I need to get iridium plug that replaces these plugs. Does anyone knowOh yeah the plug that they gave me was a CR8HIX. (Stock#7669) The electrode is about 1/4 inch too short. The overall plug is roughly 3/8Inch shorter.

I think it is a CR8EIX but on the application chart it only goes to 2005:excuseme: Thanks

I found no benefit to Iridium plugs on both of my bikes. They cost more and add nothing than is even remotely noticeable except making my wallet lighter,So I just use the CR8E.

the CR8EIX is the iridium replacement for a CR8E. The two new plugs I have here are as identical as they can be, other than the center electrodes, of course.

310404547.jpg

the CR8EIX is the iridium replacement for a CR8E. The two new plugs I have here are as identical as they can be, other than the center electrodes, of course.

310404547.jpg

grey have you noticed any benefit to the Iridium plug? The only thing I noticed is that they seemed to wear out faster than the reg plug.

the CR8EIX is the iridium replacement for a CR8E. The two new plugs I have here are as identical as they can be, other than the center electrodes, of course.

310404547.jpg

On the NGK Web-site they have a statement that says," All plugs with blue is a resistor plug". The iridium plug is black. Is the iridium plug a resistor plug?

grey have you noticed any benefit to the Iridium plug? The only thing I noticed is that they seemed to wear out faster than the reg plug.
GA, do you not have any problems with the electrical or timing with the red plugs that are not resistor?
I found no benefit to Iridium plugs on both of my bikes. They cost more and add nothing than is even remotely noticeable except making my wallet lighter,So I just use the CR8E.

I'm buying mine for $6 bucks. I heard that it is a little better. Of course thats rumor. Better starting when hot.

IIRC the irridium plug is the EIX. The chart is likely just not up to date. I think the CR8EIX is what I run in my KXF too.

IIRC the irridium plug is the EIX. The chart is likely just not up to date. I think the CR8EIX is what I run in my KXF too.

I found out and your right!!!:banghead: Thanks

grey have you noticed any benefit to the Iridium plug? The only thing I noticed is that they seemed to wear out faster than the reg plug.
No difference that I've noticed, either in wear or performance. The ignition in the YZ450 is pretty far above "adequate", so the advantages may not be that apparent. I got them to try because they were cheap at the time.
On the NGK Web-site they have a statement that says," All plugs with blue is a resistor plug". The iridium plug is black. Is the iridium plug a resistor plug?
The letter "R" in the size range indicates a resistor plug. Not using a resistor plug is risky because of the potential for ignition problems caused by EMI. You wouldn't want to see the results of a random stray spark or two that happened at 60-80 degrees BTDC at full throttle at 10,000.
No difference that I've noticed, either in wear or performance. The ignition in the YZ450 is pretty far above "adequate", so the advantages may not be that apparent. I got them to try because they were cheap at the time.

The letter "R" in the size range indicates a resistor plug. Not using a resistor plug is risky because of the potential for ignition problems caused by EMI. You wouldn't want to see the results of a random stray spark or two that happened at 60-80 degrees BTDC at full throttle at 10,000.

SO CR R being resistor?

Is this the plug that cost 20 bucks? I just recently bought one for my crf450 aand the guys was like that is 20 dollars and my jaw just dropped open. So I told him 1 sec i need to go to the car for more money.

Try pep boys...I get all my plugs there...I dont use the iridium but they sell the eix and hix line, there 4 bucks a pop.

Discount seels them for 8 bucks a pop.

Is this the plug that cost 20 bucks? I just recently bought one for my crf450 aand the guys was like that is 20 dollars and my jaw just dropped open. So I told him 1 sec i need to go to the car for more money.

I got mine for around 6 bucks!:banghead:

Yes. The C is the thread size, and the E is the reach.

The plug: cr8eix works great! NGK classifies this plug as a Premium plug. Is there an ultimate classification plug for the 450F's? Just curious.

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