2008 YZ450-White Oil Residue From Breather Tube?

4 replies to this topic
  • Boise93

Posted March 01, 2009 - 02:17 PM


The History:
I just washed my bike and changed the oil and filter on my 2008 450 at 38.0 hours with Castro GTX synthetic 4 stroke oil. I ride vet. intermediate and don't bounce the bike off the rev-limiter. I don't abuse my bike by any means.

The Scenario:
After I rode the MX track for 1.9 hours today, I noticed a few drips of white oily residue on the floor of my trailer. I inspected the drips and found they were coming from the breather tube. The bike dripped a few more drops and then stopped. The fluid was white in color, had an oily feel and had a faint smell of gasoline. I checked the oil in the case and it was perfect in color, feel, and smell. It didn't resemble the drops on the floor by any means.

The Question:
What's going on here? I'm checking my valves again this week since I'm at the 40 hour mark. 10 hours ago they were still in factory spec. Any ideas on what's happening?


  • new2blu

Posted March 01, 2009 - 02:30 PM


I see you are in Idaho---pretty cold there right now---could that possibly be some condensation mixed with the usual bit of oil blowby from the breather tube?

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  • Boise93

Posted March 01, 2009 - 02:41 PM


45 degrees today with light rain. I've ridden in much colder and wetter this winter and have never seen any white oily discharge from the breather tube. Thus my post. I just want to see if I've got a problem on my hands or if this is a normal 450 thing.

  • grayracer513

Posted March 01, 2009 - 05:17 PM


If your oil is clear, it's just condensation.

  • limitednrg

Posted March 03, 2009 - 07:26 PM


occasionally i ride a trail that has a lot of standing water and creek crossings (some are pretty deep) and have noticed the same thing. in my case its simply water going up the vent tube and mixing with the oil in the lower part of the tube (i know, i checked the top end out the first time it happened). i rerouted the tube to help prevent further incedents.

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