Plug reading

Husaberg

Help Support Husaberg:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
CheGuevara

CheGuevara

Joined
Dec 12, 2005
Messages
49
Location
Republic of Vancouver Island, Canuckistan
I just finished my first valve adjustment (@ about 3.4hrs - '05 FS650E) and took a couple pics of the plug while it was out. I've got very little experience in this sort of thing, and while I *think* it looks normal I figured I'd post the pics up for comments by those with a more discerning eye.

thanks,
-Mike

Taken with flash:

Plug_1.jpg


Taken without flash:

Plug_2.jpg
 
good question, mine always has a more dark black carbon look. That plug looks grey to me. I look forwward to the comments. I had read black is rich, grey is lean but never had a picture essay to look at maybe there is a refernce that has many pictures of plugs we can see and learn from
 
che

others will have their opinion but you can't really GIVE a plug reading till youm understand the why and how!

which came first the gymnastics coach or the judge? why both of course-one makes a good job of being the other.

first of all you should take a fresh plug and then take it for two or three runs up and down. then you should cut the ignition with the throttle still open-not easy i know-and then remove the plug wherever you come to a halt.

i lijked to take the plug home with me and have a REALLY good look at it!

right down the bottom, where you camera doesn't show is where we're interested in. the nearer to the top-the more recent the running (in other words if you pulled over at the van on idle THAT is the colour.

then you've gotta tell us what the code of the plug is and you gotta tell us the gap and what fuel you are running.

so you see, there is a lot too it. years ago vince french used to get so fed up with reading old plugs on singles he would givbe them away for free just so as he could get a reading. an old plug is no good to you.

the new kokusan ignition BTWE doesn't give a plug colour so i know you to be running SEM and the bike is a pre '03 right? :D :D

anyway. as has often been said, you have guide on the site at the owners doc abut you shoul;d get off your bum, hit the desert and practice those test runs. no excuses.

only we europeans have an excuse. i only know of 2 200 yard stretches i could run my bike.

regards

Taffy
 
Taff:

He says that its an 05.

Quite a bit of color on the plug for a Kokusan. On my 05 450 all I get is bone white. Runs very well to boot!
 
Thanks for the reply Taffy -and here I thought plug chops were mostly just for 2-strokes :)

So it's not such a simple matter to determine whether I might be running on the lean side?
 
I thought you couldn't get a proper reading on plug colour because of all the additives used in gasoline these days.
Is this not the case?
 
I still like to look at exhaust valve backsides for combustion colour. This method is really effective for letting you know if you're lean. :? I would suggest, if you're new to this full-throttle, chop technique, put a way-big main jet in your bike and watch the change in these readings as you gradually go back toward the proper setting. On a new plug, the color at the base of the porcelian will be slightly dark as that is the closest observable area near where the heat sinks into the shell of the plug. Watch out for that nasty detonation; it will kill your engine and give a really interesting and alarming plug reading! :shock: Carburetors are like beatiful women; give them what they want or they'll make your life a living hell!
 
doctorcorey said:
On a new plug, the color at the base of the porcelian will be slightly dark as that is the closest observable area near where the heat sinks into the shell of the plug.
Click to expand...

Sorry -just a bit confused here so I'll ask for clarification. Do you mean the porcelain on the body of the plug -the bit that's outside the motor? Or the bit that's insulating the centre electrode? I never would have guessed the porcelain on the body would be a factor unless it was so hot there was a serious problem(?).
 
center electrode, CG. Do a couple of runs with BRAND new plugs and you'll see it. Good Luck. Corey. :idea:
 
That's what I was hoping you were going to say :D

So new plugs and some full-throttle plug chops and I should have something by which to judge conditions. Looking online I've found a few sites about reading plug conditions, but they all seem fairly car-specific and the photo quality tends to leve something to be desired. Anyone have any links to something reasonable by which I might guage (until I can afford to buy a clue, that is)?

When doing plug chops, is it necessary to run it to redline, or just into the meat of the power curve? If I happen to hit the limiter I assume I need to start over? It's a brand new bike so I haven't really ventured over about 2/3 throttle yet and no real idea how close to redline I've come, but pretty sure I haven't quite wrung the hell out of it yet.
 
doctorcorey said

"On a new plug, the color at the base of the porcelian will be slightly dark as that is the closest observable area near where the heat sinks into the shell of the plug."

didn't quite understand that but it is usually the base of the porcelain that you view and not the bit in the open. the bit in the open is from say-the last 5 seconds of running whilst the base is the long term running or overall. therefore it is the furthest and the last to change colour.

oh and it's the first time i've seen a plug colour with the kokusan! so as long as that's his ignition and there's no oil passing the the rings/guides it means you can get a colour!

no doubt dale knew this but that's the privelage of business over private UHE bench racer!

regards

Taffy
 
Thanks Taffy - that clarifies some of what you originally posted :)

As an aside -have you got an RD as well? Just asking because I'm sure I recognise the same (or similar) ID from one of the 2-stroke forums.

Cheers,
-Mike
 
Taffy, I thought my description of the plug center insulator was clear. I, too, am refering to the wide base of the porcelian. I don't think I'm spelling porcelian right, but that base is nearest to the heat sink of the shell. That part of the insulator is the coolest, hence the darker color. On a new plug, the deposits will burn off(or not collect on) the more exposed tip( the pointy end). You con also read a lot of sign on the shell base and the ground electrode, especially on a well-used plug. :)
 
Taffy said:
no doubt dale knew this but that's the privelage of business over private UHE bench racer!
regards
Taffy
Click to expand...

Hi Taffy,
Truth be told I did not initially reply as I had nothing constructive to add regarding engine tuning based on spark plug appearance.

Personally, I tune for "optimum performance" with regard to the intended application. Providing nothing nasty is taking place (Detonation etc.) I then simply select a plug which is happy in the environment I have created via said tuning.

In the case of a commute vehicle "optimum performance" could possibly mean an improvement in fuel economy as opposed to that of increased power and / or better manners.

Kind Regards,
Dale


.
 
Or in my case "optimum performance" means (for now) everything is functioning within a range that would be considered normal and I need not be concerned about my brand new bike on it's way to a quick death ;)

Not that I have any reason to expect it is in a bad way, just trying to stay on top of any issues before they become problems.
 
I'll just add a note to my previous post. As Dale stated (notice how smoothly I dropped his name?), It is necessary that you have the correct heat range of plug to begin. No doubt some of his hot-rod motors require a different number and the heat range only reflects the rate at which a given :idea: spark plug can dissipate the heat it's exposed to. God,I'm bored.
 
doctorcorey said:
God,I'm bored.
Click to expand...

LOL - never-the-less, I do appreciate the free education. I'm not sure what plug I have in there at the moment -whatever it came stock with -and unfortunatley my pics don't show the entire number - last characters are maybe PR8E if that's of any use.
 
Since this thread seems to have come to a conclusion I hope it is ok to hijack it. A question for doctorcorey......How are the 2 Jims doing at Letko. Know Mr Lettier and Mr Koenig quite well but have not talked to them for a while. Notice their Dirt Bike ad for Bikes and Parts is no longer listed . Hope all is well with them.
dan
 
LINEAWEAVER said:
Taffy said:
no doubt dale knew this but that's the privelage of business over private UHE bench racer!
regards
Taffy
Click to expand...

Hi Taffy,
Truth be told I did not initially reply as I had nothing constructive to add regarding engine tuning based on spark plug appearance.

Personally, I tune for "optimum performance" with regard to the intended application. Providing nothing nasty is taking place (Detonation etc.) I then simply select a plug which is happy in the environment I have created via said tuning.

In the case of a commute vehicle "optimum performance" could possibly mean an improvement in fuel economy as opposed to that of increased power and / or better manners.

Kind Regards,
Dale
Click to expand...

my story is from my first manx gp in the iom in '85. i used to have a job getting the ducati to run without fouling plugs. there were reasons for this that today we would soon have sorted but in those days there was no info and i was just 24 doing my own tuning.

anyway, my mechanic and i duly ran up the engine and then in bitterly cold weather he wrestled with his pocket and swopped the cookers for the two racing plugs and off i duly went.

i came back and did a plug chop towards the start line and pulled in. because the ducati has two different cylindres and angles of carb you don't take anything for granted.

checking both plugs i gave ray a bollocking because he had pulled a warm cooker out of his pocket and put it in the upper cylinder by mistake.

so there we were studying both plugs of which one was sooty and one was white. a guy came bye and told us what was right and wrong with the plugs and then hopped it.

i blamed some jetting changes on the one good plug whilst he told me what heat range i needed. we had two different ideas.

upon moving away, another rider came over and siad that i ought to listen to him as he knew his stuff. it was 4-times world champion hugh anderson of NZ! he was there riding a G50 'clunkie!'.

so that has always left me wondering what happens to the plug colours in the same cylinder. what changes occur to the colour?

regards

Taffy
 

Similar threads

F
FE570 low idle issue, outside of the usual suspects! (I think)
Replies
2
Views
455
AussieBlue
A
W
2010 Fx450 crank no start after engine work
Replies
3
Views
487
waylon
W
I
Dream come true, sort of...
2
Replies
26
Views
2K
ihminen
I
K
AM fuel pump parts sourcing problems
Replies
1
Views
1K
o6550
o6550
2ndGen
570 longevity question...
Replies
6
Views
2K
2ndGen
2ndGen

Register CTA

Register on Husaberg Forum! This sidebar will go away, and you will see fewer ads.

Recent Discussions

Recent Discussions

Back
Top