Air from oil fill hole when engine running

3 replies to this topic
  • fastenuf4u

Posted April 10, 2006 - 03:00 PM


I never removed the oil fill plug while the bike was running before but I just did after putting on a heavier flywheel weight. Is it normal for their to be air "puffing" out of the hole, almost seems like blowby. This could have been happening for a long time but I wouldn't know because like I said above I never took it off. Thanks for any replies, and corrective actions if it shouldn't be doing that. Thanks.

  • JetPilotAlabama

Posted April 10, 2006 - 03:25 PM


Leave it on and it will not blow.

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  • fastenuf4u

Posted April 10, 2006 - 03:49 PM


Leave it on and it will not blow.

I have no problem doing that as long as nothing is wrong that could lead to a problem down the road. :thumbsup: Thanks.

  • grayracer513

Posted April 10, 2006 - 07:27 PM


Entirely normal. The piston displaces 450cc underneath itself as well as on the top. That's one reason you need a breather tube.

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