Crankcase Breather Leaking???

9 replies to this topic
  • Grashopr

Posted July 24, 2002 - 07:18 PM


My '01 426 has always spit some oil fumes out of the crankcase breather (that thick black tube hanging down right beside the stator cover). A few weeks back the zip-ty that was holding it close to the frame broke, so I used 3 zip-ty's to force it to follow the rotation of the frame all the way around, to where now it's pointing back towards the gusset in the frame right below my shift lever. I never noticed it before, but now that part of my frame is COVERED in oil. After every practice or moto I have to use over 2 pints of degreaser to get all the crudded-up oil off of the frame. My oil level isn't dropping dramatically (I change the oil every 2 rides, so maybe I'm just not giving it enough time to run itself out), but every time I clean the frame I worry about how much oil should really be coming out of this breather. Any ideas???

The 'hopper'

  • CJ_Baran

Posted July 24, 2002 - 07:26 PM


I have an 02 426 and notice the same thing. However, have not idea if it is normal or excessive. Hope someone knows about it...

  • sirthumpalot

Posted July 25, 2002 - 02:26 AM


It's normal, don't worry. You'll probably notice that on days where you spend more time in the upper RPM range you'll get more oil. Try adjusting the breather to shoot below your frame slightly so it's not coating your frame.

  • yzrider

Posted July 25, 2002 - 03:12 AM


My frame gets pretty crappy around the shift lever as well. I was thinking it was more from chain lube fling-off. Just a thought.

  • yznvegas

Posted July 25, 2002 - 05:02 AM


Totally normal.

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  • dezthumper

Posted July 30, 2002 - 06:14 PM



  • bigdrtrdr

Posted July 30, 2002 - 06:57 PM


Start your bike up and feel how much air comes out that tube and you will understand why it blows some oil out!

  • SoundChaser

Posted July 31, 2002 - 04:45 AM


I agree with everyone that this is normal to a certain extent, but if there is a lot of oil as I thought 'Hopr' described wouldn't that be a symptom of over-filling the bike with too much oil?

  • John_Lorenz

Posted July 31, 2002 - 05:00 AM


I have over filled the tank once, I saw no diff in the oil in this area. I rode pretty much the entire day with about 400cc more then I should have had.

It is normal.

Now if you add the fact that one oils the chain each ride, then the flinging snot from the chain adds to the visual of this area.

Just a thought....

  • Grashopr

Posted July 31, 2002 - 08:23 PM


EGO, I oil my chain before every race, but I merely 'WD40' it after each ride, which does make a mess, but it doesn't really 'gum up' like the oil that's on my frame..I've been watching my oil level pretty close, and even when I over fill it a bit, the amount of oil coming out of the breather hose is still consistent...I guess I should just aim the thing away from my frame....

The 'Hopper'

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