Engine oil in the airbox.

On a ride I took sunday morning I have to take about 10 miles of pavement. Those 10 miles I was 5th gear, if I open full the throttle the engine died, so I was a little behind full open. hen I stop at a gas station for a refill i notice oil driping from the air box cover (there is like a purge on the lower left corner). I removed the air filter and there was oil inside the airbox, checked and was engine oil. Checked my engine oil level and it was ok. ??? Just for the record, the engine was refreshed on december (new rings).

About 2 weeks ago a buddy took my bike. He flipped over, cut open his knee, and the bike landed on the exhaust silencer (pro circuit T4), the silencer is bended, now it point up and pushes against the rear fender. Since the new silencer hasn't arrived yet, I ride it like it is. Obviously the bent exhaust puts more restriction on the engine.

Could it be the bent exhaust the root of my problems (engine oil in the airbox and engine dying)?

I suppose that all the extra back pressure that creats could be dramatically increasing your crankcase pressure causing oil to be puched up the crankcase breather tube into the airbox. Back pressure is extremely imortant to four stroke mc's so...

you get the idea.

Just hope you did not blow a seal or anything like that.


Yeah, i'm thinking the same, and I guess all the oil going from the engine thru the carb is what is killing the engine when the throttle is wide open...

Which seal you think is more likely to be damaged?

Could be one of two simple things, just check before tearing the bike apart.

Is it overfilled with engine oil?

Is the air filter over oiled with filter oil?


Just in top mark of the dipstick, and I use uni oil for the filter...

It's kind of weird that the bike only did it in the gas station, not in th emultiple regrouping stops, not when I finally got home... And no oil leak on saturday when I did the same ride...

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