400cc oil blower

I went for a two hour ride today, riding harder than usual, to practice for a race coming up. Rode hard, and nonstop, and when I got back to the truck I noticed oil all over the left side. It appeared that there was oil blowing out the breather, splashing on the chain, and spraying all over. I would estimate that there was about 3 tablespoons of oil left in the skidpan. I checked the oil level, and it was right at the full mark, at the very end of the hash markings on the dipstick. Any ideas? Did I just overfill it and blow the excess out? Or is something bigger going on? I have blown some oil before, but not nearly this much. It is a 99 400, with about 1300 miles. Thanks.

Have no fear Buttonfly....mine used to do the same thing before I extended the breather hose past the skid plate and exited it with the other carb breather and overflow hoses. This high revving thumper has a lot of pressure and heated vapor swirling around the top end and it's inevitable for a good amount of blow-by to make it out the breather. I think that it may look like more oil than it really is, since it's mixed with a lot of dirt and dust by the time you see it on the skid plate ,IMO. Regardless, if your oil level is reading good on the dipstick, the important stuff is where it should be....in the sump wink.gif


Y2K WR400FM,Answer top tree w/Accu-Trax clamp,Pro-Tapers(CR-Hi w/ EE handguards),Devol Rad. & frame guards, Guts tall soft foam w/ ballistic cover, 14/52 w/DID VM X-Ring, Kouba-T,Michelin M-12's ft.& rr.,12 oz. flywheel weight, Zip-Ty Racing Link & Shark Fin, Cycra front rotor guard and T.M. Designworks Chain guide, buffer & chain wheels. Street legal except for the non-"DOT" tires.

Yep, my '01 WR does it a little too. NOTHING like my Husaberg did...freaking thing waterproofed my boots & pants more than once! I will probably extend that hose as suggested too.

If your oil level is correct, AND your left side is good and slick, you were probably over-filled. My bikes will dribble after a race, but no pooling.



01' WR426

99' YZ400

87' FZR1000

Uh, like twist the throttle...

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