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what carb adjustment should i try first

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i just got a 07 yz250f with less than 8 hours on it, i installed a r and d fuel screw and adjusted it for throttle response, it ended up at 2 turns, the bike has a bog etc you all know what im talking, what i want to know is should i do the o ring mod first or install a lower leak jet, im thinking the leak jet, but idk, if so what size leak jet do you guys recommend, and how do you know if the leak jet is to small or big, stock leak jet on this bike is a 80

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x2...i just bought the same year, same part, and have the same problem...lol

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the easiest way is to just put a jd jet kit in it,but this should put you in the ballpark.180main,45pilot,65leak.do the o-rind mod or just use safety wire.cheeck your float height.the 08 needle will also help out.or if you dont mind spending a few bucks,just get the jet kit,it will come complete and works well.

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Is it a bog upon acceleration or hesitation at steady throttle? If it is bog upon acceleration I'd try the oring mod or safety wire first since its the cheapest and easiest. Make sure it's timed correctly and not squirting on the slide

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i am not paying 80 bucks for a jet kit, just too much money for me, the bog is not even that bad, and when i was done adjusting my fuel scew it was at 2 turns out which is perfect, you cant just throw any pilot in the bike, if your over 3 turns out on the fuel screw you need a smaller pilot jet, if your less that 1 you need a bigger pilot jet....... and about the bog or hesitation, i think its more of a hesitation at steady throttle, and if im ideling the bike in first gear and whack the throttle it will bog, but its a race bike so i thats normal, cause no one rides it like that on a track..... this is my first 4 stroke btw came off a 125, i had my yz125 jetted like a factory bike just so crisp, the stock leak jet is a 80..... thats huge

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Is it a bog upon acceleration or hesitation at steady throttle? If it is bog upon acceleration I'd try the oring mod or safety wire first since its the cheapest and easiest. Make sure it's timed correctly and not squirting on the slide

more of a hesitation if i justcrack the throttle and hold it there it kinda like has a weird hesitating rpm

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i ran a 55 leak jet in my 09, big improvement

it sounds to me like your AP is out of whack if your hammering on the throttle and its missing or sorta coughing, I would try the o-ring mod first since its basically free and super easy

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i am not paying 80 bucks for a jet kit, just too much money for me, the bog is not even that bad, and when i was done adjusting my fuel scew it was at 2 turns out which is perfect, you cant just throw any pilot in the bike, if your over 3 turns out on the fuel screw you need a smaller pilot jet, if your less that 1 you need a bigger pilot jet....... and about the bog or hesitation, i think its more of a hesitation at steady throttle, and if im ideling the bike in first gear and whack the throttle it will bog, but its a race bike so i thats normal, cause no one rides it like that on a track..... this is my first 4 stroke btw came off a 125, i had my yz125 jetted like a factory bike just so crisp, the stock leak jet is a 80..... thats huge

I'm running a #50 leak jet and a '09 needle, both are OEM. I've also done the o-ring mod. Total cost, maybe $10.

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can you tell me exactly how the o ring mod works, i know about it and how to install it, but what dos it exactly do, and whats better the o ring mod or safety wire

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The oring or safety wire kind of forces the ap plunger down when you twist the throttle. Without it the ap is actuated by a spring and a lot of the times the spring isn't strong enough or quick enough.

You know those twist ties you use to seal bread bags or produce bags? Strip the paper off and use the wire inside that. They are free and bet you have some around in the kitchen.

As far as the JD kit $80 is not really that much. People will easily dump hundreds of dollars in exhaust systems that won't do nearly as much as a properly jetted bike. So go recycle some soda cans and save up. You will be sooooo happy that you did. Any questions just email James himself and he will reply within a day or two. Trust me the taper of the needles is what makes them special

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