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Yamaha moto 4 350 carburetor rebuild


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Hello everyone !

I'm currently rebuilding my carburetor on my Yamaha moto 4 350 1987, first time I rebuild a carb 😅 ! It was leaking fuel from the overflow and inside the intake ....

When I took off needle (the platic top part was stuck like crazy) I had a spring and inside the kit there is a spring, an O-Ring and a washer. 

Left is the needle that was in the carburetor and right is the new set (I already tried to mount it but it didn't felt right and I accidentally broke the o-ring)

Anyway, I saw in some videos and diagram that there is no spring in here. So should I put the spring back ? And where ? On top of the needle or bottom ?

20210206_225214.thumb.jpg.d827a432a0f1cf725c05921cbf7796d5.jpg

 

This is an original Mikuni carb :

20210206_230015.thumb.jpg.50ee9fe7d2bc45a5688dcf38bf1f9ccd.jpg

 

Thank you ! Also if you have any additionnal tips please feel free to share I want to learn the proper way !

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