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2012 ktm 250sx bogging on landings

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Running at sea level, 160 main 40 pilot stock needle, 65/70deg temps. It only bogs when I'm over revved kinda like a panic rev and land off of a big jump. Bogs bad enough to put you almost over the bars. Bike runs absolutely perfect other than this and never bogs at any other time. Any suggestions? I ordered a 162 main jet and will try that next.

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Forgot to add that there is another 2012 250sx that rides at the local track and he is having the exact same problem.

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All good here so far. I over shot a tabletop today and hit the flats hard and it just keep pulling. The only bog I do get is if I lug the bike in a high gear, And even then its more of a slow power to come on more so then a bog.

I could be wrong but could it be the carb float ?

I am running the red spring in the PV.

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I will put the red spring in this week as I hear it is the most preferred. I'm intermediate speed so it will probably be the best for me too. Don't know anything about adjusting the float bowl. I'm gonna give ktm world a call and see if the mechanic has ran across this problem yet. I'm sure it's something simple.

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My 2011 250XC will occasionally bog on a jump landing too. My 2008 also did it and I never could figure it out.

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I have heard that on hard landings the carb can come down and hit the engine cases and this can make it bog. Not sure if its true or not? You could try putting a rubber pad under the carb on the engine to keep it from slamming the engine? Idk, worth a shot i guess

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Might try the old trick of adding a T to the vent hoses and running a secondary vent line to the airbox. I have seen the bowl get a hydro lock from the fuel going into the vent line on landing from a jump, just as you describe.. The T will allow for proper bowl venting on landing from a jump.

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Talked to the mechanic and he thinks that it might be a float height problem. Doesn't sound very complicated like I thought, he says to make it on a level plane with the carb body. Will try this weekend and see what happens.

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Actually you need to set the carb per KTM spec. Leveling will not get it right.

As for the T I place I it right at the cab where the vent lines exit. There is a vent on both sides of the carb.. Run one line up to the air box the other back down where it originally went

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Talked to the mechanic and he thinks that it might be a float height problem. Doesn't sound very complicated like I thought, he says to make it on a level plane with the carb body. Will try this weekend and see what happens.

This, but as Zilla said...spec it!

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Zilla... I looked at the carb and there are two vent lines on each side, one comes out the side and one out of the top right above it. These two are tied in together just like a tee, I verified this by using tooth picks to make sure they tied in together. Do you think that I can run the top one into the airbox instead of running the tee's? I'm guessing that by doing this I'm trying to pull a small vacuum on the carb? Also looked at my manual and it doesn't say anything about float height. Can someone post a link or tell me what the measurement is in the service manual?

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I just bought a 250 XC and have the same problems... not real happy with a brand new bike having problems like this.

Im also an Int level guy and another friend rode it and noticed the same thing without me mentioning it to him. I really hope this problem can be resolved.

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Definently not an isolated problem. The only other bike at the track does the exact same thing, it's only a month old. The 1st thing he did was come running asking if I had this problem and since the first ride I have.

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I had a local Pro with the same problem. After trying many jetting combos with no luck. I raised the float level slightly and problem solved.

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I had a local Pro with the same problem. After trying many jetting combos with no luck. I raised the float level slightly and problem solved.

I had a float issue with my service honda.. I have not taken this bike apart (its 4 days old) but Is it a situation where you have to bend the little tab that retains the needle valve?

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Great! Can someone give a brief write up on how to adjust float level and the measurement that this bike needs.

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I had a local Pro with the same problem. After trying many jetting combos with no luck. I raised the float level slightly and problem solved.

How much did you raise it. 1/16".... 1/8"?

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I had a local Pro with the same problem. After trying many jetting combos with no luck. I raised the float level slightly and problem solved.

Hey man, seems like you got the fix, mind elaborating a bit for the guys on here that might not be as mechanically inclined? :lol:

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