thats what it seems like but i put my timig back to stock and it runs a lot smoother then i put in a bigger main
spark plug color
- Thread starter roadkill
- Start date
Hmm.. I run +4 timing too. But mine runs fine. I'm just trying to get the carb dialed in properly. I didn't a WOT run and checked the plug its still crispy white maybe cream in color so I didn't even bother to chop it. I'm dropping down on main jet so I can lean it out I guess I'm hella rich. But it doesn't feel like it at all. Rides great
plug color for me isnt telling me anything cuz it seems the richer i went the better it runs im not sure whats up ik for sure i dont have any leaks
yo i might be wrong but i think i heard going fat on the main means its covering up for an air leak. hopefully someone chimes in help us both :-[
You have to do a plug chop and/or use an oscilloscope to look down at the bottom of the insulator to get results. Like I said previously, the "fuel ring" is what you are looking for in terms of "jetting". You warm up, swap plugs, and run WIDE OPEN THROTTLE all the way up to 5th or 6th gear with the throttle all the way open. The results are noticeable right away after you chop the plug. Excess deep brown/black is PIG RICH. While it depends on your engine setup and while it isn't ALWAYS the case, the pics Zwiser showed earlier in this thread is PIG RICH. It's so rich that the excess fuel that isn't being burned and is being essentially wasted is even building up on the insulator tip. You want to get a CLEAN BURN. A "clean burn" for increased power is a light wisp of tan for the fuel ring and little to no fuel should be anywhere else on the insulator as the engine is running hot enough to burn off excess fuel around the insulator tip. Here are 2 examples.....1 is quite rich with a 330 main. The 2nd is still a little rich with a 320 main by my standards but tolerable. A 310 main would probably work even better but I didn't have a pic of one. Don't mind the far left one. The middle one is the 320 and the right one is the 330.
320
330
320
330
i got the idea of what color to look for but since my plug is practically still white after a WOT in all gears, does it mean im supposed to go lower on my main? bc i ran 160/45 middle C, and 150/40 3rd C, and i think it ran good but better at 160 set up. both set ups seem about the same.
It's pretty hard to stay completely white at the bottom of the porcelain. Even in lean cases, you have a gray color from oil burn off. You need to go up in main though if you essentially have no fuel ring........way up.
thats weird. when i ran the 160/45 middle C it was bogging out in 1/4 and 1/2. then i lowered the needle (3rd c) it was fine. i guess i'll lower the needle all the way down to lean it out more. the biggest main i have is the 160
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you dont change more then one setting when tunning the carb cause if you change more then one thing and it gets better or worse you dont know witch one did it you only change one thin at a time for a wot plug chop if it looks lean you only have to change the main jet anyway the main jet has nothing to do with 1/4 or 1/2 throttle only full throttle get a bigger main if the plug isnt reading right
so WOT chop is for the main. got it. so im plug chopping the wrong way. 
the bogging out at 1/2 and down would mean my pilot is too fat then right?
(plz excuse if im jacking the thread this IS related to plug chopping and coloring)
the bogging out at 1/2 and down would mean my pilot is too fat then right?(plz excuse if im jacking the thread this IS related to plug chopping and coloring)
here is a old plug of mine it ran very well tad on the rich side but i liked it like that wasnt realy any sort of bog or anytthing but i dont see whats wrong with runing a little bit rich on a trail bike as long as its not boging or anything like that remeber your mototr will last longer a little bit on the rich side but heres the picture
its a nice chochlate cardborad brown sorta color like 99lrd's are between these pictures you should get a good idea of how they should look
its a nice chochlate cardborad brown sorta color like 99lrd's are between these pictures you should get a good idea of how they should look
so WOT chop is for the main. got it. so im plug chopping the wrong way.
(plz excuse if im jacking the thread this IS related to plug chopping and coloring)
pilot is idle to 1/4 throttle then needle and clip postion is 1/2 to 3/4 then main is WOT
remeber you also have an air screw if its less theb 1.5 turns out you need a bigger pilot if its more then 2.5 turns out you need a smaller pilot
here is a old plug of mine it ran very well tad on the rich side but i liked it like that wasnt realy any sort of bog or anytthing but i dont see whats wrong with runing a little bit rich on a trail bike as long as its not boging or anything like that remeber your mototr will last longer a little bit on the rich side but heres the picture
its a nice chochlate cardborad brown sorta color like 99lrd's are between these pictures you should get a good idea of how they should look
haha it's such a biotch to get a camera to focus on a spark plug isn't it? X(
so WOT chop is for the main. got it. so im plug chopping the wrong way.
(plz excuse if im jacking the thread this IS related to plug chopping and coloring)
That depends where the "bogging" is occurring and how it is occurring. If it's a BWAHHH beating on hollow drums sound, it will be lean. If it stutters or sputters it's rich. It's also helpful to think of how that relates to your carb while it functions. Does it occur at half throttle up to 3/4?......1/2 to full?....etc. It's most likely a needle setting that's off. You may have to go up or down on the needle, but figure out the main first.
haha it's such a biotch to get a camera to focus on a spark plug isn't it? X(
not as bad as geting the lighting right so it doesnt turn the hole thing white but you cant have to little light or the pictures to dark to see anything right lol
As a side note, for those interested, you have to get creative with lean and rich noises. For a lean sound, think of a water pump when it doesn't get enough water and makes that hollow sound. For the rich side, think of a popcorn maker from hell popping away.
