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Best 300 jetting

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My weather in ohio 700' elevation is moving into 40's soon. Should i mess with all 3 circuits or just bumb up pilot?

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Pwk 36mm keihn. 35pj 172m

All manuals are rich, cant use this as gospel

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Try 40-42 pilot jet, nedj or necw suzuki needles third clip from top and 170-180 main jet.

Check your slide and see if its 6.5 or 7. I prefer 7 for its a bit crisper down low.

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Try 40-42 pilot jet, nedj or necw suzuki needles third clip from top and 170-180 main jet.

Check your slide and see if its 6.5 or 7. I prefer 7 for its a bit crisper down low.

wow! No where in my manual does it call for a 40pj, or beyond a 178mj, this us a 2016 te300. Even at artic temps at sea level.

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The bike is rich im guessing, it got a little spooge out tail pipe. Im on a 178mj and 38pj, its winter here 30deg at 700ft, its manual spec besides suzuki needle. I think if anything i should go 1 up leaner than maual calls for at any temp or elevation to lean it out to run perfect but im new at this bike. Im coming off a yz450f 4t

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I am runnin a 42pj in my tc250 and 170mj and i am at 60f at sea level.

The colder you go the richer you need to be. The manual is for reference and are mainly lean.

Try 40 pj, 180mj and turn the air screw out 1.5 turns...

Change your needle to a suzuki one, necw

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Maybe you havent read what i just posted. And generally manuals are rich btw, its a safety measure

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I read what you wrote, and given all the variables i am giving you a starting point. Start with the pj open the air screw, if rpm is still raising after two turns out then go with smaller size, if rpm is stops raising after one turn go with larger size.

The needle is difficult but use necw third clip down from top, and for wot start with a 165 and check plug, if white go larger if black go smaller, if brown, bingo you nailed it.

Changing the pj or needle will effect main jet so start down low and work up...

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Here are MXA’s recommended jetting specs for the 36mm Keihin PWK carb (when changed, stock specs are in parentheses):

Main: 158

Pilot: 40 (42)

Needle: N1EH

Clip: 4th clip from top (3rd from top)

Air screw: 1-1/2 turns out

Notes: We found the stock 250SX jetting to be in the ballpark, but as with all of our two-strokes, we spiced up our 91-octane pump gas with a splash of VP C-12 just to ensure fuel quality.

For colder weather you will need larger mj

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Here are MXA’s recommended jetting specs for the 36mm Keihin PWK carb (when changed, stock specs are in parentheses):

Main: 158

Pilot: 40 (42)

Needle: N1EH

Clip: 4th clip from top (3rd from top)

Air screw: 1-1/2 turns out

Notes: We found the stock 250SX jetting to be in the ballpark, but as with all of our two-strokes, we spiced up our 91-octane pump gas with a splash of VP C-12 just to ensure fuel quality.

For colder weather you will need larger mj

thanks but this doesnt apply to my 2016 te300. Jetting never goes over 38pj even for north pole

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I threw my stock carb away and went with a Lectron Jetless carb.....no more playing with settings and jet sizes when I'd rather be out riding. I have over 600 miles on it now from 1100 feet to just over 7600 feet and it has never been touched.

 

just my .02 cents.......

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The Lectron with new throttle cable etc came out to a little under $450.00. I have buds that have sold the stock carb on craigslist for $250.00 ish. So that actual cost is very doable.

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