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Discussion Starter · #1 ·
if my sparkplug is black b/c of to rich would just changing the main jet fix this or would i have to change the other jets too.. please let me know
 

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i beleive the spark plug has more to do with the main jet. what are you running? if you have basic mods (baffle out lid off and cam mod) and you are running a jet bigger than a 170, you are probably to rich. if you have all that but like a pipe and air filter and bigger than a 190, you are too rich. this all depends on your elevation and mods you have done. list your mods and what everything in the carb is set at and we will see what we can do to help ya out.


*edit* the plug will also get black if you let it idle for too long and foul out.
 

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Originally posted by YFZ@Feb 12 2004, 10:33 PM
I think it depends. You could be rich anywhere in the powerband. Are you running rich on the top end can you tell?
:stupid it depends...... go hold ur throttle in a certain spot for a couple mins(i.e. 1/4 throttle, 3/4 throttle or w/e ) and if its black then that setting is rich.... if its like nuthing, its lean... thats the only way u can really tell
 

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Discussion Starter · #5 ·
i have a hmf full exhaust,cam mod,lum airbox no lod,and i have right now a 175main,48pilot,gyt-r needle 4th clip,2 turns. this is the setting that makes my sparkplug black. i was thinking of switching to a 168 main but is this the only thing i have to change????????????? also i am at sea level and the temp is about 30 or 40 outside
 

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Originally posted by tmm403@Feb 12 2004, 11:05 PM
i have a hmf full exhaust,cam mod,lum airbox no lod,and i have right now a 175main,48pilot,gyt-r needle 4th clip,2 turns. this is the setting that makes my sparkplug black. i was thinking of switching to a 168 main but is this the only thing i have to change????????????? also i am at sea level and the temp is about 30 or 40 outside
that sounds good........ i dnt know where ud be messed up...... maybe 3rd clip on needle? :what let one of the gurus tell u :rock
 

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How black and where?


Even if it is black, going all the way down to a 168 may be too lean, there is a 170, and 172 in between there to try,

Personally I would go with the 170 but this all depends on how black and how you were riding it.

If it just sat and idles for a couple of minutes then you pulled the plug well that means that its rich on the pilot. But that is not really a problem cause its not too rich and the extra gas helps starting. The pilot is only used to about 1/4 throttle.

You need to do a couple of actual plug chops, and just overall "feel" the bike.

Can you hit the rev limiter in 4th? 5th?
 

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Discussion Starter · #8 ·
well with the 175 main i have in there now i was just going up and down my street and up nand down my driveway thats it. i did before try a 170 main and it was black also. i will try the 170 again and see if that helps but mainly all i was doing was rolling the gas and then gunning it. like you would do to try to get the front end up. it just sucks b/c from all this jetting changes i already used like 6 plugs. alright i hope this sloves my problem.
 

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Originally posted by tmm403@Feb 13 2004, 04:11 AM
well with the 175 main i have in there now i was just going up and down my street and up nand down my driveway thats it. i did before try a 170 main and it was black also. i will try the 170 again and see if that helps but mainly all i was doing was rolling the gas and then gunning it. like you would do to try to get the front end up. it just sucks b/c from all this jetting changes i already used like 6 plugs. alright i hope this sloves my problem.
That is not how you do a plug chop.

You need to get somewhere where you can run it at different throttle settings for like 1/8-1/4 mile then imediatley shut the engine off and w00ter into neutral. Slow to a stop and check the plug right then and there.

Do not idle to a stop kill the engine at speed.

You will never know where you are rich at by doing them the way you are.

But if I were to have to guess then I would say the pilot or needle cause the last thing that you are doing is going slowely up into the drive.
 

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Discussion Starter · #10 ·
WELL I DID DO THE THING U SAID ABOUT GOING FULL THROTTLE AND SHUTTING OFF THE ENGINE AND ROLLING TO A STOP BUT WHEN I DID THIS WHEN I HAD A 180 MAIN IN I CHECKED THE PLUG AND IT WAS WHITE. BUT THEN AGAIN I GOT HOME FROM RIDING IT AND THE NEXT DAY I TRIED TO START IT AND IT WOULDN'T START AND WHAT U KNOW IT WAS THE PLUG THAT WAS BLACK. SO NOW WHAT
 

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Well that means that your main is ok or even alittle lean.

How did you ride it after you done the plug chop and the plug was white??

It did not just magically get black without starting it and running it again.
 

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Discussion Starter · #12 ·
OK what i did was first i tried a 170 main,45 pilot,2 turns,clip 4 gyt-r needle. that made the sparkplug black. next: 180 main,45 pilot,11/4 turns,clip 4. thats when i did the full throttle test. very good but a little boggy when i first hit the throttle. so maybe that was the airscrew casuing the bog. and that when my sparkplug was white when riding and then black later on. then i thought i would try a 180 main,50 pilot,2 turns,clip 4. same thing sparkplug white but when i gave it throttle it bogged. my guess it was the pilot to big. so then i went back to when it ran good with little bogging and try to go from there. and also after i tried it with a 170 main the sparkplug was white when doing the test but again black later on. and this last jetting i did was 175 main 48 pilot 2 turns clip 4 and it ran awesome except for the damn plug. so please tell me what i'm doing wrong from all of this.
 

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Originally posted by tmm403@Feb 13 2004, 10:48 AM
OK what i did was first i tried a 170 main,45 pilot,2 turns,clip 4 gyt-r needle. that made the sparkplug black. next: 180 main,45 pilot,11/4 turns,clip 4. thats when i did the full throttle test. very good but a little boggy when i first hit the throttle. so maybe that was the airscrew casuing the bog. and that when my sparkplug was white when riding and then black later on. then i thought i would try a 180 main,50 pilot,2 turns,clip 4. same thing sparkplug white but when i gave it throttle it bogged. my guess it was the pilot to big. so then i went back to when it ran good with little bogging and try to go from there. and also after i tried it with a 170 main the sparkplug was white when doing the test but again black later on. and this last jetting i did was 175 main 48 pilot 2 turns clip 4 and it ran awesome except for the damn plug. so please tell me what i'm doing wrong from all of this.
I think you are worrying about the plug too much. If you jetted it and it ran awesome it will be all right. As long as you are not too rich that you are fouling plugs just leave the jetting to when it runs awesome. I am not a mechanic or know much about engines I just started jetting so if anyone disagrees let him know. I just think you should jet it to when it runs awesome and leave it alone. Do not worry about the plug. It is very hard to get the plug to be brown meaning absolute perfect jetting.
 

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Discussion Starter · #14 ·
the only thing about getting a black plug is that it won't start. first time i tried jetting i kept trying to start it both push button and kicking it and it wouldn't start. finally i took the plug out and that was the reason. i just don't want to keep taking the tank off just to put a new polug in everytime i want to go out and ride. i just want to know what i might have to change.????
 

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I am in the process of jetting mine before season starts. I have not got my plug the color the way I want it, yet. (If that is possible on this machine to see brown). But I do know that a 48 pilot will stop the problem everyone is having on bottom end, when you stab the throttle. 48 piot is the cure!!!!! It will take the throttle and love it.
 

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so pull the choke half way out on start up. If your jetting right, it will choke properlly, warm up, then run right...
 
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