Oil (Foam) in breather tube

Is it normal for my 01' WR426 to dribble foamy oil from the breather tube on the left side of the motor (the breather tube that comes from the valve cover)?

After a ride I get about a thimble full of foamy oil that drips from this tube after I park the bike for a few minutes, I also notice that it is sort of blowing back on the frame below my footpeg/shift lever area.

Is this normal?


01' WR426,YZ timing,EMP #2,#48Pilot,#100PAJ,#172 Main,BK mod,stock pipe-no baffle, open airbox,Gray-Wire Pulled,K&N Filter, throttle stop mod,CA Street Legal,Pure SuperMotard 17 in. wheels, 15/46 gears,ProTaper bars,

Scream Man,

Yes, it is very normal for this to occur. I asked this same question two years ago. It sure don't look right, but it IS normal.

As an FYI, when you start your bike, the engine sucks through this tube. While running, it blows. Many of us have re-routed this breather vent, some into the airbox, others by the steering stem. This gets it out of the way of WATER which will get sucked into the engine, if you should stall your bike in water. I did, and I now have a scored cylinder as a result.


'99 WZ/YR (you choose!) with ALL YZ mods, de-octopused, DSP Doug Henry airbox w/ velocity stack, FMF PowerBomb header, Stroker SX-1 silencer, SS front brake line, OEM YZ tank, IMS YZ seat.

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