Hotter plug. What's it gonna do?

[redroost85]

My ride is running a decent amount on the rich side. When I was done at the Honda shop a while ago, the tech guy said I could run a hotter plug to help compensate. I am running a new NGK dspr8....something or other. He said if I go down to a 7 that it may help. Can anyone help me on this? What will the hotter plug do for me, good, bad, ugly? Thanks guys!:D

[redroost85]

Come on EXriders experts....I need your help so I don't make myself look like a jackazz!:D

[Stevie-D]

ya..this past winter the ex was runnin real crappy and a tech guy at my dealorship sold me a something..."8" plug. its ran really good ever since. i believe that the 8 runs hotter than the 7:macho

[Rip_Tear]

JMO, you should make the quad not run so rich, whether its changing jets or carb set up etc... The plug may help, it can't really do much to hurt it.. but you really should get the mixture fixed :D The dealer should have told you/done that.

[redroost85]

Stevie-D, the tech guy told me that the 7 is hotter than the 8. Ahh, I should just fix the mix in the first place, lol!:devil

[Joequadracer]

Lower the number the hotter the plug

[Big - D Racing]

Dpr9z runs hotter than Dpr8z.

[shamisc]

Originally posted by Big - D Racing
Dpr9z runs hotter than Dpr8z.

THAT'S RIGHT !! :macho

[infantry317]

Yep, I just switched from the stock 8 to a 9 for woods racing to keep the engine cooler with my 275lb butt on it! :devil

[Stevie-D]

Stevie-D, the tech guy told me that the 7 is hotter than the 8.

;) whaaaaatever...lmao..im gonna half to go to my tech guy and tell him that he's wrong...oooh...thats gonna be fun:devil

[86atc250r]

With NGK plugs the lower the "heat range" number, the "hotter" the plug. This is not the case with all brands.

The heat range of the plug tells how fast it transfers heat from the center electrode to the head. The faster the heat moves away from the center electrode, the colder the plug.

The plug must be hot enough to burn off deposits and keep itself clean or you risk fouling. However the hotter the plug, the more likely it will be to start preignition which is very bad, or even burn the piston. The tip of the plug should run between approx 900°F and 1500°F

You can verify if a plug is "colder" or "hotter" than another by looking down between the threads and the center electrode, the deeper it is before you see the "floor" the hotter the plug.

It's always best to correct a tuning issue instead of "band-aiding" it with a heat range change. Heat range is not meant to correct tuning issues.

Here's an image from NGK that may help you visualize

[SGA]

86atc250r Is right. What you need to do is get the jetting right. Changing the plug is not the correct way to compensate for a rich or lean engine.

[Joequadracer]

When I posted I was refering to NGK spark plugs, I should have been specific.