Spark Plugs...

Fouled my first plug today (too much lugging around maybe, or rich low speed circuit?) and I accidently tossed a CR8E in my gear bag, although I another stock plug. The CR8E is the same dimensions and identical in appearance. It is what I run in my FZR600. I tossed it in, and ran it back to the truck through about 10 miles of sand dunes, mostly rolling hills. Question is, what did I hurt, or can I run this plug? The stock Denso U24ESR-N is fouled. Can anyone give me a background on plugs, and the like? Thanks.

Nevermind, I missed the mention of the CR8E in the manual in my frantic flipping through. You can run the CR8E, as per the manuals two choices (NGK or Denso). And now a new question, is Denso short for Nippendenso? I remember hearing that name somewhere, but I don't know where... thanks.

It is short for Nippondenso. I use to swear by these plugs, but can no longer find them. I am presently running a Splitfire in my WR.


99 WR, all YZ mods, de-octopused, OEM YZ tank and seat, jetting by Clark.

Moab bound for 2000!!

Are Splitfire plugs hype or real? Can you REALLY tell the difference from a Denso or NGK?


I used to own a 1976 Kawasaki KS125 dual purpose, rotary valve induction 2 stroke. It came stock with an NGK. The main jet was off, and being a 14 year old kid, maintenance was filling it up with gas. I put in the ND Hot U plug and the bike immediately ran great. The plug had a good burn color to it.

My 91' CR had a cold fouling problem. I switched to a projected tip NGK plug as recommended by Eric Gorr. The fouling was histroy but the burn wasn't perfect. I switched to the ND Hot U equivalent and my CR ran perfect too. One ENTIRE season, I used the same plug!

The Hot U has a u shaped groove in the electrode. ND claims the U groove helps shape the burn and contain the spark better. It may be hype, but I do know for a fact every bike I have put them in, which is every bike I have owned (7) since 1977, runs very good with a good burn. I run them in my car too. I know Dennis Kirk sells ND, but I am not sure if they have the right plug. The Splitfires are cheap ~$3.50 through Dennis Kirk. I figured if this plug can keep me from fouling out miles from home/vehicle, it is worth every penny.


99 WR, all YZ mods, de-octopused, OEM YZ tank and seat, jetting by Clark.

Moab bound for 2000!!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now