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Unstable idle kymco jr100

Benimosto

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Joined
Jul 29, 2026
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3
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Antananarivo
My kymco jr100 has a very unstable idle.

When i accelerate (a little boost) it stays at like 4-5k rpm for several seconds before going down and nearly shutting down.(mixture screw tightened to the max). I tighten the idle screw and the rpm stays very high.

I tightenned the mixture screw to de max and loossen it 1,5 turn. Now the idle stays at 4k rpm.

I loosen it more, even worse. The idle goes up and down on its own.

Here are all the specs of my scooter:
55mm cylinder (SEE)
Bigger head (idk but it has bigger intake valve) that says kymco LAB4
CVK 24 carburator
Direct cone intake
Whatever this exhaust is (picture)

Please help me, i had 0 experience jumping into that project. I am open to any advice about anything (pls don’t be harsh😭🙏)
 

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