Plug Color

[2004LEBanshee]

Ok After a day of hard riding can i look at the plug and get an accurate reading. Same as the plug chop or not. Just wondering what a plug that is too rich looks like after a day of rideing hard. From looking at the top mine looks pretty dark Brown. I am wondering because you guys stated for my mods that 380 is too much so I just got some 340 and was wondering if I should bother switching them out. I really haven't noticed it running poorly or anything so any suggestions are appreaciated.

 

Also If I chop this plug after ridding for hours is the main jet still the only thing that colors the base or does the whole plug pretty much turn the same color all the way up the electrode.

 

PS Dont tell me to run a WOT test because I live in the city and there is no where to do it. I want to stay a little rich when I go riding sunday and then it will be too late if it is lean. I can only hit 3rd on my rode.

 

Thanks.

[Fever]

The plug color will not be accurate like this because if your low speed is rich and your high speed is lean (for example) idling in the garage or slow speed riding will show a rich spark plug even though when you open it up it is lean....can you take a day and haul it out of town?

[sredish]

Ok After a day of hard riding can i look at the plug and get an accurate reading. Same as the plug chop or not.  Just wondering what a plug that is too rich looks like after a day of rideing hard. From looking at the top mine looks pretty dark Brown.  I am wondering because you guys stated for my mods that 380 is too much so I just got some 340 and was wondering if I should bother switching them out.  I really haven't noticed it running poorly or anything so any suggestions are appreaciated.

 

Also If I chop this plug after ridding for hours is the main jet still the only thing that colors the base or does the whole plug pretty much turn the same color all the way up the electrode.

 

PS Dont tell me to run a WOT test because I live in the city and there is no where to do it.  I want to stay a little rich when I go riding sunday and then it will be too late if it is lean. I can only hit 3rd on my rode.

 

Thanks.

Only way to accurately tell how the main is jetted is by running wide open throttle to at least a long 5th gear, then pull clutch and kill motor. Check then. That is the only accurate way to check your main jetting. Once your main jetting is good, then adjust the pilot and such to perform good. You'll be set.

 

What happens, is your riding hard, busting ass, and say, your main's lean. Your done riding, and putt putt back to camp for a quarter mile or so, and your pilot may be a little rich, or just right. When you get to camp, and check the plug, it's nice and dark. Thats because right before you shut it off, it was running good off the pilot jet. or needle. The main jet pushes most of the fuel through at hard riding, 1/2 to full throttle, so the only way to get a true reading on the main, is to pull the main as hard as you can, like wot. The higher gear will work the carb the hardest, if your ganna be lean, you will be in 5th or 6th gear at wot. If 3rd is all you can hit, then that will have to work, just make sure you pull totally wide open and kill it quick.

 

You have to check the plug at the ceramic base, not the top. The top will generally be darker because it's farther in the chamber. Check down kind of inside the threads, where on a new plug would be white, underneath the electrode. The base can and a lot of times will be different than the "top".

 

If it's running lean, it will be running pretty smooth. A lot of people make the inaccurate assumption that it's running good, so it must be alright, it will run really smooth when its lean. For instance, I haven't checked my plugs in a while, but I thought it was running really good, but the exhaust started having a little bit different smell (anyone know what I'm talking about), so I did a plug chop. I went from 185 to 190 on the mains, and 52 to 55 on the pilot, haven't checked yet, but it was much leaner than I liked before I changed, and it wasn't like that three months ago, so go figure.

 

Hope this helps. When in doubt, go a tad richer than you think, rich won't hurt, but lean will kill your machine.

 

Scott

[ledofthezep]

When in doubt, go a tad richer than you think, rich won't hurt, but lean will kill your machine.

That's the theory I've lived by & I've yet to have to crack my motor open.

 

 

 

 

...knock on wood.

[2004LEBanshee]

There probably isn't a way that I'll be able to check it before I ride again so I should just leave it till I can. Is there a way that I can hurt this by being to rich. I mean it's at 380.

[FULL_METAL_JACKT]

damn......

 

 

after read'n that shit like 10 times

i think i understand

[Ducman]

Ok After a day of hard riding can i look at the plug and get an accurate reading. Same as the plug chop or not.  Just wondering what a plug that is too rich looks like after a day of rideing hard. From looking at the top mine looks pretty dark Brown.  I am wondering because you guys stated for my mods that 380 is too much so I just got some 340 and was wondering if I should bother switching them out.  I really haven't noticed it running poorly or anything so any suggestions are appreaciated.

 

Also If I chop this plug after ridding for hours is the main jet still the only thing that colors the base or does the whole plug pretty much turn the same color all the way up the electrode.

 

PS Dont tell me to run a WOT test because I live in the city and there is no where to do it.  I want to stay a little rich when I go riding sunday and then it will be too late if it is lean. I can only hit 3rd on my rode.

 

Thanks.

380 sounds realy big, 340's sound closer to what should be the correct size mains probably still a little rich. You most likely haven't felt it bog from being jeted to rich on the mains yet because you haven't tried to rev it out in a high gear with the throttle pinned. Doing a plug chop only works when you install a new set of plugs, start it, then run it up through the gears one time at WOT, pull in the clutch and shut it down while still rolling, then remove the new plugs, put the old plugs back in, then go chop the plugs that were only ran for the short WOT test. You can bring a hack saw and some vice grips or something to hold the plug while you saw on it with you when you go riding out of town. Do this check first thing after you get it good and warmed up. What you are looking for is a 2mm (approx 1/8 inch) carmel brown band at the very base of the electrode. The majority of the electrode will still look white because it was only ran such a short time. If you dont get any brown band or much less than 2mm at the base then you are too lean, if you get much more than 2mm or the whole electrode is dark brown then you are too rich. I would probably put the 340's in and try them. If they turn out to be lean, which I doubt, then put the air box lid on to cut down some air flow and try again. If its rich with the 340's then your motor will still be safe, it just wont run as good as it should. I wouldn't run it at WOT at all if you find that it is lean.

[2004LEBanshee]

Thank you guys for the info. Not to be mean but I knew how to the the WOT test I just can't do it anywhere around my house. I understand that I can't figure my jetting exactly with out doing it. I just want to be a little closer then I am now. Basicly what I am trying to do is set my bike up in a condition that I know is for sure rich. That is why I was planning on putting in the 340's and running it that way. Basicly what I wanted to know is if there is any way that I could be lean with these. And If it is possible then what size should I put in or should I just leave it because I know it's for sure rich now.

 

Thanks for the replys guys.

[sweetshee4312]

if there no where to ride it wot, take the road for one run, but make it count

[Ducman]

If you can do you jetting where you are going to ride, ie you dont get the bike too dirty or it isn't too windy or rainy, get some other jets 310, 320, 330 and give yourself an extra hour or 2 and bring all the tools you need and a large tub to work over so you don't drop any small parts in the dirt. Or if the 340's are rich but not so bad that you are fouling plugs or cant even get into the band at WOT or are overheating, ride it and put smaller jets in when you get home. If its just slightly rich then go one size smaller, if it's real bad, bogs and wont go into the band then go 2 to 3 sizes smaller.

[Trouble T]

I have FMF Fatties K&N air filter and about 500 feet above sea level. I dialed mine in with a 290 main jet. 380 IS WAY WAY WAY too large.

[Nighty]

toomey t5

boyesen reeds

jetkit (needle) currently 340 and upping to 360 main

+4 timing

K&N

 

 

340 was lean .. i hope 360 will do the trick.

i am at 0 sea level.

[2004LEBanshee]

Finally put in 340's went to a local hick town took the bike off and took off down one of there streets got home cut the plugs a bearly saw a light brown ring way at the bottom. So I just left them however I did change my needle before i went to fourth from the point wich I later found out was the wrong direction but it ran great, so to be safe I just put it back in the middle.

[Ducman]

Finally put in 340's went to a local hick town took the bike off and took off down one of there streets got home cut the plugs a bearly saw a light brown ring way at the bottom.  So I just left them however I did change my needle before i went to fourth from the point wich I later found out was the wrong direction but it ran great, so to be safe I just put it back in the middle.

Good job, sounds like you are pretty close, you might want to go to 350's if the band is less than 2mm. Did you measure the brown band at the base of the electrode? Your only looking for 2mm, that is less than 1/8 of an inch, so check it, you may be just right. In my experience i have found that if your dialed in slightly on the lean side, the power is good, but the bike tends to heat up a little faster on hill climbs and situations where your in the band under heavy load for a long time. Slightly on the rich side and it runs cooler and no change in power.

[2004LEBanshee]

I just looked for the color. As for the heating up, Yes I know the temp guage isn't the most accurat because it measures collent. But I beat the crap out of it and it never went over 130. Also when I did the test it was around 30-35 degrees out. This sunday when I go it's supposed to be like 57 high so I figured I'd just leave it. thanks for the input.