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Discussion Starter · #1 ·
I know there are a million threads about this, but I want one to help me specifically on my sled. The mag I am running a 190 main 50 pilot 1 1/2 on the air screw, and I am at what I believe after reading the other threads is the perfect color brown, the PTO has 185 main 50 pilot 1 1/2 turns on the air screw, and it looks a little more white then I think it should.

Now these plugs have about 10 miles on them, do I need to run them some more to get an acurrate reading.

Question, which way should I adjust it to get it a little more rich?

Sled is a 99 700 RMK.
 

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10 Miles should be plenty for an accurate plug reading.

Good thing to do to is get it on a track stand, run it WOT and hit the kill switch, then get your reading from there.
 

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^^^A track stand you trust! You should really check the plugs in a few throttle positions. You may be lean on top but good at idle and midrange. Pilots are probably good cuz 50 is pretty big. You can raise the needle and help the midrange out or make the main jet larger to fatten up the top end.
 

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Discussion Starter · #4 ·
When I bought it it had 190 mains across the board. I was told these older 700s you want the pto one step down from mag side
 

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Cardboard brown is the goal in a 2 stroke. If the reading was taken after a WOT run, then you want to increase the main jet to richen your mixture. If the reading was taken in the midrange, you can raise the needle to richen that. And of course if you took the reading at idle you will need to increase the size of the pilot jet.

Get your mains dialed in first, then needle position, and finally pilot jet.

Don't forget that as temps get colder your mixture will get leaner which is why you need larger jets for cold temps
 

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Discussion Starter · #6 ·
TriumphoverU said:
Cardboard brown is the goal in a 2 stroke. If the reading was taken after a WOT run, then you want to increase the main jet to richen your mixture. If the reading was taken in the midrange, you can raise the needle to richen that. And of course if you took the reading at idle you will need to increase the size of the pilot jet.

Get your mains dialed in first, then needle position, and finally pilot jet.

Don't forget that as temps get colder your mixture will get leaner which is why you need larger jets for cold temps
Sled has ACCS, do i still need to change it for temps?
 

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Do you have the stock pipe? I haven't heard of running staggered mains on those engines. I would bring that 185 back to 190.
 

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Discussion Starter · #8 ·
98rmk700 said:
Do you have the stock pipe? I haven't heard of running staggered mains on those engines. I would bring that 185 back to 190.
yes stock pipe, in fact i think it is written that way in the owners manual, and it is how they came from the factroy
 

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Discussion Starter · #9 ·
I just did a WOT run and they were almost exactly the same, I had to check again just to make sure I didn't take the same one out twice. They are the color that I would call cardboard. My pen light didn't quit get in far enough to read the wash, but it appears to be about a 1/4-1/2"
 

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Discussion Starter · #11 ·
I want to get the rest dialed in first, and I got the top end done. Now I want to do the mid, then the idle. I seem to have a lowend bog right now should I get everything dialed in and see where I end up or try and get that fixed. I know it runs little lean at idle, if i adjust the air screw some, will it mess the rest of what I have done up?
 
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