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Slight bog when at idle?

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Hey so i have a ktm 300 recently put a jd jetting kit in but im stilling having an issue if i get the bike fully warmed up then let it idle and if i give it a quick handful of throttle there is a slight bog for like half a second then it revs normally, my air screw was like 3 turn out.... i put it back to what JD jetting recommends at 1.5 turns out but didn't get a chance to test it tonight my question is does that mean its running to rich or to lean should i have backed it out some more?

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The air screw has nothing to do with your symptom. The air screw is for idle and just off idle only.

Your issue, assuming you can duplicate it under load, in the right gear, on the trail, is a lean condition of the main jet or needle.

If you turn the throttle on any two stroke too far, at too low of an idle, you will get this same symptom to some extent.

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Sounds normal to me. You can try raising your idle speed a little though no one normally grabs a handful of throttle at idle when riding, the engine is typically well above idle, unless they are in the driveway, just reving it up.

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1 hour ago, William1 said:

Sounds normal to me. You can try raising your idle speed a little though no one normally grabs a handful of throttle at idle when riding, the engine is typically well above idle, unless they are in the driveway, just reving it up.

My buddies bike is 2 years older and when it took it for a spin and at idle I didn't feel any bog

 

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On 9/7/2017 at 9:21 PM, THE KRAN said:

Then your main jet is TOO BIG

that doesn't make any sense the main jet has nothing to do with idle to low rpm...

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48 minutes ago, Hucks said:

that doesn't make any sense the main jet has nothing to do with idle to low rpm...

Actually, no jet has anything to do specifically with rpm, without including throttle position.

WOT issues are the main jet, regardless of rpm.

Edited by THE KRAN

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15 minutes ago, THE KRAN said:

Actually, no jet has anything to do specifically with rpm, without including throttle position.

WOT issues are the main jet, regardless of rpm.

if it was anything it would be the pilot jet right? i was told the main jet controls 50-100% throttle range..... also like i mentioned i installed the jd jet kit so my "jets" should be spot on i was thinking more of a air/fuel screw or lack of air flow to the intake... last night i messed i with the screw a bit more and it got better im around 2.75 turns out and like @William1 said a little bog down low is normal on a 2t if it persists i will definitely investigate the main jet thanks for the tip!

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The air screw controls the pilot jet. It is a trim.

Make sure you do NOT adjust it unless your idle is very low. If you adjust it with a higer idle, you will be comensating for the slide being too high in the first place.

If you start at one turn out, lower the idle, you should be able to raise the idle with the AIR screw. 

If it takes more than 2 turns, your are too rich. Less than 1, you are too lean, on the pilot jet.

That's it for the pilot.

 

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4 hours ago, THE KRAN said:

The air screw controls the pilot jet. It is a trim.

Make sure you do NOT adjust it unless your idle is very low. If you adjust it with a higer idle, you will be comensating for the slide being too high in the first place.

If you start at one turn out, lower the idle, you should be able to raise the idle with the AIR screw. 

If it takes more than 2 turns, your are too rich. Less than 1, you are too lean, on the pilot jet.

That's it for the pilot.

 

If I go more then 2 turns in it won't idle 

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