Spark Plug

[scottzx7rr]

Hey I see that everyone recommends the a NGK CR8E or CR9E plug but I was wondering what everyone feels if there is a risk of running a CR7E plug. I understand that it is a hotter plug and I was worried that it might burn the piston.

I have about a case(yes over 500 of these plugs) because it is the plug that I run in my roadrace bike(Ninja) and figured that I could use them.

I am a diehard NGK user and agree they are far superior to the other brands.

Thanks in Advance.

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Scott #431

Some Fear Racing "Cause if you don't have any you ain't going fast enough"

'99 YZ400F(Coming to a Theater near you soon)

'92 ZX-7R and '97 ZX-7RR

"Doesn't hurt till the bone is exposed"

"When cut do you bleed green? I do!"

Pics

[This message has been edited by scottzx7rr (edited 12-06-2000).]

[Taffy]

100% go with the 7 no problem.

you won't damage anything IMHO.

if you run it lean & balls out it will start to misfire & you'd beter go back to an 8.

Taffy

[Hick]

Scott,

I take it you’re worried about pinging that gets bad enough to ruin your piston? I remember reading somewhere that each “range” corresponded with 100 degrees (Celsius) of plug temp., that seems like enough to cause preignition (or am I just confused about heat ranges again?)

I’m no expert and I’m not sure if I’d risk it just to save a few bucks but maybe you could try one for a few progressively longer rides and then see if the tip looks like it has gotten too hot. I would probably just stick with the 8 (I did foul a 9 once though so maybe there is sufficient wiggle room for a 7).

As for your 500 CR7Es, are you familiar with the concept of “Sunk Cost?” ?

Sorry to be of so little help…

[This message has been edited by Hick (edited 12-06-2000).]

[scottzx7rr]

I do understand. Being a former roadracer for Kawasaki I am a little anal about maintanance and change the plugs after ever race/practice so I bought quite a few to keep around. I get a better deal by buying so much at once. That will normally last about 6 months.

With some of the things I have heard about the bike and oil starvations/high temps I was worried about the additional temps generated by the plugs. I know that as you modify a engine you want to go to a colder plug range with the general rule of 1 range colder for every 50hp gained.

Pre-Ignition isn't really a concern as I typically run race fuel in my bikes.

Thanks for the input.

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Scott #431

Some Fear Racing "Cause if you don't have any you ain't going fast enough"

'99 YZ400F(Coming to a Theater near you soon)

'92 ZX-7R and '97 ZX-7RR

"Doesn't hurt till the bone is exposed"

"When cut do you bleed green? I do!"

Pics

[This message has been edited by scottzx7rr (edited 12-07-2000).]

[Taffy]

what a load of bollocks boys! jesus!

one heat range per 50hp!!!

the plug is there to work at a certain temp in the cylinder head right.

but it isn't the plug that creates the temperature is it!

it's the mixture strength. if you're running lean the plug won't put up with it-simple. it's too exposed isn't it.

if you're running rich it copes BETTER. THE IDEA IS THAT WHILE YOU'RE RUNNING RICH YOU USE THIS PLUG TO GET YOU IN THE BALL PARK WHILE YOU MAKE THE NECESSARY MODIFICATIONS TO YOUR JETTING.

when you feel the engine is purring like a kitten & you've leaned it off a bit, when you've done a few clean thrashes & it's smooth, crisp & runs clean you go back to the 8's.

if you just toodle around & don't do 1 mile straights you won't have a problem. the plug will le you know soon enough.

Taffy

[Me]

geee dhaa my owners book says to run 10w-40w motor oil in my 4stroke but i have a case of automatic trany fluid do you think i should just use the case of trany fluid instead????????? it also says to use 10w shock oil in my shock but all i have is this 5gal bucket of paint thiner i think i'l run that in my forks too

[Hick]

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