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BIG carb on KDX?

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Everyone is boring out their carbs to 36mm and installing the divider plate. What if I went and got a 38mm carb? A 125 is 75cc's smaller and uses a 38mm. I think that putting a 38 on a KDX might give a significant power increase. What does everyone think?

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Everyone is boring out their carbs to 36mm and installing the divider plate. What if I went and got a 38mm carb? A 125 is 75cc's smaller and uses a 38mm. I think that putting a 38 on a KDX might give a significant power increase. What does everyone think?

Which KDX do you own? 200 or 220?

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The 200 already has the big carb in it. You have a 35mm and you could have it bored to 36 but I don't know that it would be worth it.

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but a 125 uses a 38mm and is 75cc smaller, and handles the huge carb fine. It has almost no bottom end, but the KDX does and if you went and put a big carb on the kdx, it would have some bottom end still, and kick a$$ on top, right? and I havent gotten the RB carb or head mod yet, but It's just hard to imagine that a 1mm boreout would make a very big difference. I understand that the divider plate helps a lot with low end, but wat about the high RPM's? Does it make a difference? And also, would I have to get a veforce3 reedcage, in order to really feel the power?

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A larger bore carb would add top end power at the expense of bottom end. I believe that's the idea with the divider plate in the RB carb, to retain bottom end. I don't think a 38mm carb would fit in the stock reed-side boot.

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A larger bore carb would add top end power at the expense of bottom end. I believe that's the idea with the divider plate in the RB carb, to retain bottom end. I don't think a 38mm carb would fit in the stock reed-side boot.

That's exactly what I was thinking, but don't you think I could find an aftermarket one to fit?

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I don't know of one, but that doesn't mean one doesn't exist. Call Jeff at frpoffroad and ask him. If anyone would know he would.

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Why bother feeding the bike more fuel/air when it isn't necessary? The manufacturer put that size carb on for a reason, and the only reason I see for going to a bigger carb would be if your engine is ported and polished, or bored extensively larger.

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a kx125 probably puts out close to or more HP than a KDX and it's because of the carb size.

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