KDX 220r with 35mm carb jetting question

[sixteendohc]

I have a 98 KDX 220r with FMF pipe and silencer. The jetting is perfect right now. If i move the the 35mm KDX200 carb, should I bel able to just swap the jets over or will I need to play with the jetting again with the new carb?

 

[mandark1967]

move the jets over and you should be okay

 

[sixteendohc]

From what I understand, I can use any kdx200 carb from 1988 and up?

 

["REV"]

The jets are the same. BUT, they are not neccesarily going to work well on your bike, you have 10% more displacement.

 

[sixteendohc]

well I'm going to move my jets over to the new carb

 

[kdxtaz]

NO!!! The jets from the smaller 220 carb (33mm?) will be too lean in the larger 200 carb (35mm). Engine displacement has nothing to do with it. You should start with no smaller than a 155 main and work from there.

 

[adam728]

kdxtaz is right!!!!

The air velocity in the larger carb is slower, which creates less signal at the jets. This means you need larger jets to work properly.

Stock main with a 33mm carb is a 145. After boring it to ~36mm I run 152-158 depending on temperature and elevation. Or I run a 175 when in the dunes, but that's a whole different ballgame.