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05 yz250f athena 290cc big bore jetting

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wondering on rough idea of jetting guides...i know

nothing is certain...but in general...a basis maybe..

detroit michigan area...

see yz250f forum for my original thread...modded...exhaust blah.blah

vp c12 straight..

thanx ...anything guys

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lean the main a few...highly doubt..in fact i know not too...

need more fuel bro... why do you think every big bore kit that come with carbs...come with LARGER carbs and LARGER jets...the c12...its high compression..not

super high.. but c12 is just fine...the research octane is only 104 and the bike is

jsut going to run cooler...ryunnig cooler retains horsepower..not losing any...

i need just some jetting ideas...basis..thanx but no thanx man

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From what I've read on this jetting forum, a person should drain that VP racing fuel from the bowl after your done riding. Other than that have done a spark plug check to see how rich you actually are. A 188mj for a 290cc bike seems pretty rich.

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lean the main a few...highly doubt..in fact i know not too...

need more fuel bro... why do you think every big bore kit that come with carbs...come with LARGER carbs and LARGER jets...the c12...its high compression..not

super high.. but c12 is just fine...the research octane is only 104 and the bike is

jsut going to run cooler...ryunnig cooler retains horsepower..not losing any...

i need just some jetting ideas...basis..thanx but no thanx man

ok,good luck to you. :banghead:

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lean the main a few...highly doubt..in fact i know not too...

need more fuel bro... why do you think every big bore kit that come with carbs...come with LARGER carbs and LARGER jets...the c12...its high compression..not

super high.. but c12 is just fine...the research octane is only 104 and the bike is

jsut going to run cooler...ryunnig cooler retains horsepower..not losing any...

i need just some jetting ideas...basis..thanx but no thanx man

It is clear that you know little or nothing about jetting. Burned is the moderator for the jetting forum, he speaks the truth about lowering the main.

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I put a 262cc kit on my 250f and had to go down 2 on the main. It has nothing to do with the carb. The motor creates more "suction" if you will..I went from a 175 main to a 170.. But this is just me.

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alright....ladies...im not jsut jetting the main...tahats not all you jet...

that is top end purely top end...yes a plug check i know...its perfect at

the main...got off with the phone with athena...they said specificly...

1 to 2 sizes up at least...its a keihin fcr...a nice carb...thanx ladies for nothing

i thought some peaople knew some things around here..i need new...good info

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Why did you bother, it sounds like you have it figured out anyway.

Never to smart to learn !

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