question on a 1999 yz400f

1 reply to this topic
  • charlie coleman

Posted March 10, 2013 - 01:01 PM


on the right side of the motor there is a little hole and i am trying to figure out what it is for and why it is there ! i guess i should be more specific it is actually in the head just above the cylinder

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  • grayracer513

Posted March 11, 2013 - 06:31 AM


It's the drain and vent for the spark plug well.

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