Which Spark Plug to Use?

9 replies to this topic
  • Matt_the_Fat

Posted June 26, 2001 - 05:04 AM


Greetings from sandy, muddy, cloudy, sunny Michigan. I searched the archives for plug suggestions and came up short. I just bought a replacement(NGK CR8E) for my fouled out stock Denso plug and was hoping to get some feedback on plug choices. I heard that NGK's w/ ***EG are supposed to be platinum, but I couldn't get ahold of one. What's the scoop, oh knowledgeable thumpers?


  • Mook

Posted June 26, 2001 - 07:54 AM



I am going through the same thing you are (looking for the best plug). I have a buddy here on TT that I race with who has the 99 YZ400F and the 01 YZ250F. Based on his experience the splitfire 430B??? works for him. I am going to check the numbers again with him then order one for my WR250F to try.

hope this is helpful,

2001 WR250F - Snorkle out, t-stop cut, grey wire mod, YZ timed, DR.D Pipe, Ty Davis/IMS seat and tank, handlebar hot start, panoram computer, Mich S-12 Rear/ Mich starcross MS2 front, Ty Davis rad supports, Scotts Damper and triple clamp w/ Protaper bars, stock jetting, fuel screw 1.75 out, that's about it...

  • *mike68*

Posted June 26, 2001 - 08:20 AM


How often should you change them. I got ovet 1000mi on my 01 426 and it still runs like a champ.

  • Hurricane

Posted June 26, 2001 - 08:51 AM



I went to my dealer the other day and asked for replacement plug for 98 WR and he gave me NGK CR8EVX. I figured it was what came with bike since I just got it but when I pulled the plug and looked in my shop manual it has the NGK CR8E. The box for the CR8EVX says Platimum on it. I wasn't sure if I should use the platinum one or not. Is there a difference? Will the bike run hotter? Any suggestions would be helpful.


  • Ga426owner

Posted June 26, 2001 - 09:23 PM


My 2 cents:I have tried both the NGK CR8E & the CR8EIX -platinum plugs. I found the CR8E works everywhere - meaning all altitudes. The Platinum CR8EIX worked great in one location/altitude but fouled out in lower Altitudes during kickstart (all over 1 weekend)The CR8E was not affected. The difference in altitude was minimal all in NGeorgia area. I was not able to tell any real difference in performance although technically the platinum should be a better plug. It is around 4-6bucks also.
I have never used any other brand.

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  • Ga426owner

Posted June 26, 2001 - 09:24 PM


Sorry the CR8EIX is not Platinum, it is Iridium

  • Dennis'_WR426

Posted June 26, 2001 - 10:31 AM


I live in Michigan also. I understand about the weather beleive me. I own a WR426, and had no problems with plugs as of yet. However, did you change anything in the carb? Just thought I would ask.

  • Matt_the_Fat

Posted June 28, 2001 - 07:57 AM


I'm all stock except the airbox lid, throttle stop, and grey wire. Everything is running flawless right now. I'm enjoying it while I can.

  • z4me

Posted June 28, 2001 - 08:17 AM


Originally posted by *mike68*:
How often should you change them. I got ovet 1000mi on my 01 426 and it still runs like a champ.

I have heard that the electrode can get fatigued and break off after time. What I heard was to change them at least every 1000 miles.

- Sean

  • vincegatcore.com

Posted June 28, 2001 - 08:34 AM


I had a cr8e in for two years.(2200 miles)
then I cut the grey wire and the plug fouled 20 miles later(changed it on a mosquito infested trail).
should have done it sooner :)

I'm pretty sure there is no connection.
I'm sure my plug was just too old.

I am now replaceing my balencer drive gear straight key.(mine is all smashed up)
hope it is the source of my engine rattle.

finally a place to get great info.
Big thanks to everyone at thumpertalk :D :D :D


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