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xr 400 mikuni pumper jets

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my dad bought a xr 400 a few months ago that already had the mikuni 36mm pumper on it. he has trouble starting it on trails if he stalls or crashes. what jets does anyone suggest? the bike has an xrs only slip-on, and stock motor.

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If it is hard to start only after dumping it it's not the jets.

Keep your fist out of the throttle when kicking it.

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I'm guessing your near sea level? In that case, XRs Only most likely would have set the carb up with 130/15 jets.

Any air box/filter mods?

After a dump, use the manual decomp to clear the cylinder before trying to restart.

Restarting with the Mikuni is a little different than the stock carb. As always, start your kick from TDC. But near the bottom of a good hard kick, wick the throttle open slightly like you were going to rev a motor a little. Not so much that you activate the pump.

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After a dump, use the manual decomp to clear the cylinder before trying to restart.

I do the same thing but i hold manual decomp + full throttle + half a dozen kicks and then usually it will start first kick like when cold.

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sorry im around 1500 ft and i dont know what jets are in it at the moment because we havent pulled it apart. The snorkel has been removed

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