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Carb to Intake boot, shape effect performance?

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This is an 02 cr 250, with 36mm kehin, 03 head,03 boot,03 intake boot, and 03 reeds. It's basically an 03

the carburetor's fit in the intake boot didnt look quite right. The fact that there is a valley all around where the carb meets the boot. Seems like if where a smooth better fit it would flow better. Does this make sense?

You can see the lip of the carb I colored in blue.

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The stock carb was 38mm maybe the smallet size is whats causing your issue how dose it run

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It runs good. The 36 is supposed to make better low power with a little sacrifice up top. The way to have best of both world I'm told is to taper bore the 36 to 38 or 39? Found it on dicks racing website under carb mods. They also add an adjustable intelajet thing but I have herd mixed reviews about the adjustable jet. Either way I'm poor and can't afford the mod.

I agree the 36 makes more of a "lip" inside the intake boot. My question is there any performance to be had if it was a smooth transaction?

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Ok, seems that there is a flaw in the 36mm carb fitment then.... My next question is how would someone go about making a smooth transition in the intake boot?

Maybe some kind of apoxy that could withstand the fuel/oil mix. Also use grease so it wouldn't adhere to the carb..? Any ideas?

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Iv been thinking about this all day. Iv also been reading too many posts on port work and epoxy, I don't know if making a mold of the inside boot connection and shaping it for better flow is possible.... Anyways I thought I was maybe on to something...

Does anyone have experience with carburetor taper porting? Is this something I could maybe have a machinist do? Keeping the 36 intake and making the top 38?

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That will be little if any obstruction due to the direction of the airflow. There's a "step" as the hole gets bigger from the carb to the intake boot. This may cause some minor turbulence, or it might not. And if there is turbulence, it may or may not make any difference in the way the bike runs. Testing is the only way to know for sure.

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