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arby
13th December 2004, 01:15
I getting ready to do a stage 1 to my 04 883C. SE air cleaner, 170 main jet and Vance & Hines s :confused: traight shots. What color should the spark plugs be if the jetting is correct. Also should I start out with a new set of plugs.
Bob

cantolina
13th December 2004, 01:17
For the price of plugs, and the diagnostic value, go ahead and replace them.

Mine stay pretty clean (light tan) but I've been told I might be running a tad lean...

Your manual has a better explanation...

arby
13th December 2004, 23:33
thanks
Bob

stevo
14th December 2004, 00:11
OK I've finally got the sh*ts with everyone thnking ya just have a quick look at the colour of ya plugs and that tells ya everything

I have a small magnifying glass and a good light in my tuning kit.

Here's a link...read it

It's race orientated, so most of the fuels and rpms are not what ya goin to be usin BUT it's a good startin point......I just did a google and found it, had a quick read and it looks like it says most of what I was gonna anyway.

http://www.dragstuff.com/techarticles/reading-spark-plugs.html


I normally run the timing band on the bend for street use, past the bend and it's too far advanced for street.

txsporty
14th December 2004, 00:39
Stevo,

Great article!!! Learn something new everyday!!! :D

cantolina
14th December 2004, 00:41
OK I've finally got the sh*ts with everyone thnking ya just have a quick look at the colour of ya plugs and that tells ya everything
<snip>

Thanx Stevo, GREAT information! My favorite, (but not the most informative!) excerpt:

"Other than installing thermo-coupler sensors in the combustion chambers the only real way that you know what is happening inside your engine is to read the spark plugs."

:clap :cheers :clap

skooter
14th December 2004, 01:03
Yup! It is a good article. I found that very interesting too. I saved that one and I'm going to refer to it again. I've got some others I'm going to share that with.
Thanks stevo.

collinsb
14th December 2004, 01:13
Thanks Stevo! Good stuff to know!
Billy

stevo
14th December 2004, 10:53
There's a bit more to it than that particular article for street use BUT I make a livin out of this stuff.

SO I'm not gonna tell ya everything :)

The problem comes in knowing who is actually gonna listen and do something with it, otherwise it's just a waste of my time that I don't have.

That one was easy tho I just did a google and that was close.

My head on the other hand is a bit harder to google ;)

whiffy
14th December 2004, 19:17
Thinking of Google here are some other links

http://home.clara.net/dave.moore/plugs.html

http://www.biker.force9.co.uk/archives/features_sparkplugs.htm

Dont forget, if you are gonna read your plugs, cut the engine at the desired throttle opening and coast to a stop. Use the mixture ring at the base of the Ceramic to take the reading, not the end at the electrode.....

I hope I dont see too many Sporty riders flat on the tank on full throttle for several miles being chased by the cops..."but officer, I was only checking my mixture settings" will not be a way to avoid a ticket or a ban....:laugh

I still think a dyno is a better place to read the mixture.....but it does cost more than a flashlight and mirror...make sure you use the correct bulb, cos if it's a 'yellow' light then you will be reading the wrong colour.....


Whiffi

cantolina
14th December 2004, 21:30
<SNIP>
Dont forget, if you are gonna read your plugs, cut the engine at the desired throttle opening and coast to a stop. <SNIP>
Whiffi

Personally, I want to know what my plugs say is happening AS I RIDE MY BIKE. Not on a dyno, not at a "desired throttle opening"....

My plugs, read correctly, will warn me of any impending internal problems far before anything else....

Anything else is just benchmarking, yes?

stevo
14th December 2004, 23:32
The fuel/air ratio and ignition advance changes at different engine speeds..

It is impossible to acurately read a plug over a range of speeds.

When I'm dialin in right to the Nth degree I'll use a box of plugs, so I keep puttin fresh ones in to get an acurate reading....at different throttle openings.


If ya just ride around for a week and then pull the plugs you will not get an ACURATE assesment of what is happening inside your engine as one range will overlap the other.

It's only if you have major problems in there that much will show.

This why I posted the info in the first place..and why I think plug chops and fine tuning should be left to those who understand what they are doing...

BUT if ya gonna do it yourself at LEAST read and learn what is what first.