Spark plug reading

Racer x · September 27th, 2009, 06:34 AM

I thought I would start a thread about spark plug reading. I know something about it .But probably just enough to get in trouble .

These are the plugs out of my 250 ninja . I use NGK CR9E the stock plug is a NGK CR8E . The CR9E is a cooler plug than the CR8E .

I went to the CR9E because I noticed the tip of the CR8E was just starting to melt after a pass at Maxton .
I have the rare opportunity of being able to make a 100 mph one mile run and stop and pull the plugs . I park my van near the finish line for that reason.

The last run I made I had a spark plug issue . I contribute to installing and removing the plugs to often , But it gives a perfect view of a plug after the thread is gone.

If you look at the broken plug there is a line of darker color at the base and the tip is lighter. That line is very important. Ignore the color .(it looks rich and it is but that is mostly because it was missing. And I ran that plug on pump gas. Not race gas . The other plug is much lighter. And the A?F ratio was a tad rich on the dyno.)

The lighter tip is telling me that the the temperature of the mixture is hot enough to burn the carbon . if Carbon is left it will deposit on the insulator

nate-bama · September 27th, 2009, 07:34 AM

I've allways been told that a cardboard color is what you want in a plug...and either white or black is lean/rich . I'm curious as the diffference between cr8e and a cr8hsa

Racer x · September 27th, 2009, 07:57 AM

Quote:

Originally Posted by nate-bama

I've allways been told that a cardboard color is what you want in a plug...and either white or black is lean/rich . I'm curious as the diffference between cr8e and a cr8hsa

You are correct that the cardboard color is what you want from a street plug . Where prolonged idle and choke use will discolor the insulator . Once it turns color it wont get very white again.
But you want to see how far down the insulator the color is before it changes to dark . That is telling you the heat of the combustion.Remember that the plug will not change the mixture it only indicates the mixtures temperature. If that temp is to high . Then you would need a cooler plug to dissipate more heat and not melt.

For tuning main jet mixture it is best to start with a new plug . and do a plug chop . By "plug chop " I mean putting plugs in the bike warming it up under slight load then full throttle for as long as you can . then stop pull the plugs and look at them .

It was easy to do this back in the day with air cooled bikes . The 250 ninja makes this a little more difficult.
Are the HSA's the plug with two ground electrodes?

nate-bama · September 27th, 2009, 09:27 AM

sorry for the pic quality

randomwalk101 · September 27th, 2009, 10:22 AM

racerx,
so what happened? too hot and it melted everything? so all the prong/thread etc are floating in your engine now?

Racer x · September 27th, 2009, 11:38 AM

I went to the dyno to tune the bike . After I got home I pulled the plug to make sure the tips were OK . I put them back in . Maybe I over tightened it. Or they where week from being pulled to many times I don't know . But at the track at full throttle the engine misfired ,so I went to my pit to check out the engine . When I pulled the wire up the plug came out with it . It took a while to get the thread out . A fellow racer gave me an easy out and it fit and removed the thread intact.From the looks of the plug . Knowing how the dyno AF ratio was The rain was barely holding off . So low pressure led me to go from 118 to 115 jets .

Alex · September 27th, 2009, 01:04 PM

Racer X - you have a current-gen bike, right? I'm moving this thread to that tech section; right now it's in the pre-gen tech section.

/thread moved

Racer x · September 27th, 2009, 05:00 PM

Quote:

Originally Posted by Alex

Racer X - you have a current-gen bike, right? I'm moving this thread to that tech section; right now it's in the pre-gen tech section.

/thread moved

Sorry about that It will be good for any bike though . When ever someone asks if they should re jet when changing the exhaust . The best answer is to pull the plugs and see.

This is the same engine with a Yoshi full system . With 110 jets . it is about right acording to the A/F ratio gauge I have on my dash.
I need to find a better way to take a close up photo of the plugs.

Alex · September 27th, 2009, 05:14 PM

Does your camera have a "macro" setting?

HKr1 · September 27th, 2009, 05:45 PM

Quote:

Originally Posted by nate-bama

I'm curious as the diffference between cr8e and a cr8hsa

Different reach for sure. E is 19mm (3/4") & H is 12.7mm (1/2")

Quote:

Originally Posted by Racer x

Are the HSA's the plug with two ground electrodes?

K = two electrodes. Like CR8EK

NGK web site has lots of nice info:

http://www.ngksparkplugs.com/tech_su...e.asp?mode=nml

http://www.ngksparkplugs.com/tech_su...x.asp?mode=nml

randomwalk101 · September 27th, 2009, 08:06 PM

Quote:

Originally Posted by Racer x

This is the same engine with a Yoshi full system . With 110 jets . it is about right acording to the A/F ratio gauge I have on my dash.
I need to find a better way to take a close up photo of the plugs.

How do you have an a/f gauge on your dash? I mean how do you mount the o2 sensor. Just drill/weld into the header? Is it a wide band sensor?

Racer x · September 28th, 2009, 02:37 AM

I mounted the A/F gauge in the dash with an O2 sensor in the header. It is a cheep one . The wide band with memory is about 400 bucks.

I will have to check out the NGK web page tonight .

Racer x · September 28th, 2009, 02:59 PM

This is the link to NGK Tech page. It is long but for those interested in basics of engine tuning it . It may be something to print out and hang in the bathroom.

http://www.ngksparkplugs.com/tech_su...x.asp?mode=nml

nate-bama · September 30th, 2009, 06:05 PM

I had to run my bike for a week with my emergency plugs in it. cr7hsa, i had them laying around the local kawi dealer sold them to me as oem but my god don't ever use these

gamma500 · October 7th, 2009, 07:53 PM

Quote:

Originally Posted by Racer x

I mounted the A/F gauge in the dash with an O2 sensor in the header. It is a cheep one . The wide band with memory is about 400 bucks.

I will have to check out the NGK web page tonight .

How did you find enough room in our header to mount an 02 sensor...the darn pipe is only 1" in diameter ?

September 27th, 2009, 07:34 AM	#2
nate-bama North Alabama Mtn. ryder Name: Nate Location: Alabama Join Date: May 2009 Motorcycle(s): 2006 Posts: 537	I've allways been told that a cardboard color is what you want in a plug...and either white or black is lean/rich . I'm curious as the diffference between cr8e and a cr8hsa __________________________________________________ QTRltrPWR

September 27th, 2009, 01:04 PM	#7
Alex ninjette.org dude Name: 1 guess :-) Location: SF Bay Area Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much. Blog Entries: 7	Racer X - you have a current-gen bike, right? I'm moving this thread to that tech section; right now it's in the pre-gen tech section. /thread moved __________________________________________________ Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)

September 27th, 2009, 05:14 PM	#9
Alex ninjette.org dude Name: 1 guess :-) Location: SF Bay Area Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much. Blog Entries: 7	Does your camera have a "macro" setting? __________________________________________________ Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)

September 30th, 2009, 06:05 PM	#14
nate-bama North Alabama Mtn. ryder Name: Nate Location: Alabama Join Date: May 2009 Motorcycle(s): 2006 Posts: 537	I had to run my bike for a week with my emergency plugs in it. cr7hsa, i had them laying around the local kawi dealer sold them to me as oem but my god don't ever use these __________________________________________________ QTRltrPWR

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September 27th, 2009, 10:22 AM	#5
randomwalk101 self wrencher Name: john Location: houston Join Date: Dec 2008 Motorcycle(s): 08 250r and 07 600r Posts: A lot.	racerx, so what happened? too hot and it melted everything? so all the prong/thread etc are floating in your engine now?

September 27th, 2009, 11:38 AM	#6
Racer x ninjette.org certified postwhore Name: Eric Location: Iowa City Join Date: May 2009 Motorcycle(s): 2008 Kawmeracchi 350 2010 Project X Posts: A lot. Blog Entries: 54 MOTM - Sep '18, Feb '16	I went to the dyno to tune the bike . After I got home I pulled the plug to make sure the tips were OK . I put them back in . Maybe I over tightened it. Or they where week from being pulled to many times I don't know . But at the track at full throttle the engine misfired ,so I went to my pit to check out the engine . When I pulled the wire up the plug came out with it . It took a while to get the thread out . A fellow racer gave me an easy out and it fit and removed the thread intact.From the looks of the plug . Knowing how the dyno AF ratio was The rain was barely holding off . So low pressure led me to go from 118 to 115 jets .

September 28th, 2009, 02:59 PM	#13
Racer x ninjette.org certified postwhore Name: Eric Location: Iowa City Join Date: May 2009 Motorcycle(s): 2008 Kawmeracchi 350 2010 Project X Posts: A lot. Blog Entries: 54 MOTM - Sep '18, Feb '16	This is the link to NGK Tech page. It is long but for those interested in basics of engine tuning it . It may be something to print out and hang in the bathroom. http://www.ngksparkplugs.com/tech_su...x.asp?mode=nml