TOPIC:

I was at the auto parts store today and they told me
ngk plugs are backwards, meaning a number 8 plug would be hotter than a number 9. my manual says that a 9
plug would give a modest performance gain which
would be wrong. This wouldnt be the first time
my manual has lied to me, what i want to know has anybody ran an 7 ngk?this would be on the 900
76 kz model. these

Go the NGK web site, it will explain it all

1045

Your manual said using the wrong heat range would give you a performance gain? Hmmmm

If you have a 1976 KZ900, use NGK B8ES ONLY or use Nippon Densu (ND) plugs. The NGK are much easier to get around where I live and that is the only plug I use.

The heat ranges are sort of backwards on NGK plugs with the 7 range being "hotter" than the "8".

The purpose of a spark plug is:
1. fire spark
2. conduct heat out of the combustion chamber
3. burn hot enough to burn crud out of a combustion chamber

People occasionally use hotter plugs to burn off excessive carbon build up caused by a weak ignition (weak spark) or improper air/fuel mixture. This is a band aid fix and itself leads to problems. Use the correct heat range and fix problems causing the sooting. Changing the heat range to a hotter or colder range MAY be warranted in extreme temperature conditions but in ordinary use, the Kawasaki recommended heat range for your bike works best. In your case that is a B8ES plug!

wiredgeorge wrote:

Your manual said using the wrong heat range would give you a performance gain? Hmmmm

If you have a 1976 KZ900, use NGK B8ES ONLY or use Nippon Densu (ND) plugs. The NGK are much easier to get around where I live and that is the only plug I use.

The heat ranges are sort of backwards on NGK plugs with the 7 range being "hotter" than the "8".

The purpose of a spark plug is:
1. fire spark
2. conduct heat out of the combustion chamber
3. burn hot enough to burn crud out of a combustion chamber

People occasionally use hotter plugs to burn off excessive carbon build up caused by a weak ignition (weak spark) or improper air/fuel mixture. This is a band aid fix and itself leads to problems. Use the correct heat range and fix problems causing the sooting. Changing the heat range to a hotter or colder range MAY be warranted in extreme temperature conditions but in ordinary use, the Kawasaki recommended heat range for your bike works best. In your case that is a B8ES plug!

What he says , unless you are have a problem ........
ALWAYS tune to your plugs

Everything you need to know about spark plugs by NGK

...they told me
ngk plugs are backwards, meaning a number 8 plug would be hotter than a number 9...

NGK plugs are not backwards. Increasing number corresponds to cooler plug for all(that I've ever seen) brands.

-Duck

If I were using an NGK "8" on an 8:1 compression ratio engine, (Stock 1976 KZ900) should I move up to an NGK "9" if I make modifications that result in my compression ratio moving to 10:1?

when i went to buy plugs for my kz, only one was available from ngk.....and that was the iridium....it didn't show a standard plug for it

The NGK website shows a B7ES for a KZ440 LTD.

www.ngksparkplugs.com/index2.asp?country=US&nav=a0000

BARNEYHYPHEN wrote:

If I were using an NGK "8" on an 8:1 compression ratio engine, (Stock 1976 KZ900) should I move up to an NGK "9" if I make modifications that result in my compression ratio moving to 10:1?

I would stick with 8's unless you have a need to move up the range. I've run 8's in most of the Z1's I've ever owned - the only exception is my turbo bike - I run 9's in that as the bike runs VERY hot. The key is your plug color - if it's a nice tan color then stay with 8's.

I will occasionally switch a bike to 7's if it's burning oil - just to try and keep the plugs clear.

Willo46 wrote:

The NGK website shows a B7ES for a KZ440 LTD.

www.ngksparkplugs.com/index2.asp?country=US&nav=a0000

yea, i know...but for some reason kawasaki was only showing the iridium plug

Jeff, Thanks for the advice. The #20's are on their way back to you.