So I have been fiddling with Bonnie (my '00 savage) for a week tryin to get her to start up. Turns out I just needed to tighten up the connection on the ignitor box. Then this morning I fired her up to ride to work and she would not stop backfiring. After she warmed up she started to sound a lot better. I started the ride and on each de-acceleration there was a few loud backfires. It was not running like this before today.
     Then about 3 miles from home I felt a warm liquid running down my leg. I checked and no I had not peed on myself.   Then I looked over the side of the bike and saw oil streaming out of the crankcase breather hose filter. I have removed my air-box and ran the breather hose over the top of the engine  and back out the front so it sits right by my left knee. I have put 1000 miles on the bike since I removed the air-box and started running this setup and have never had a problem with oil finding its way out of the hose. I immediately turned around and limped home paying very close attention to the sound of the engine in case it started to seize up or run too hot.
    I am clueless, any suggestions as to what the problem is or what the troubleshooting steps might be. I am almost to the point of total rebuild. I dont want to go that way because I just finished a rebuild 1000 miles ago.

I have not changed the oil in a few hundred miles or so. Also I did not notice any smoke out of the exhaust. I have a very free flowing short muffler with a  homemade baffle so if there had been smoke it would have been noticeable soon.

Lupo wrote on 09/24/10 at 08:43:11:


Oil return is the cam chain well.
And the oil breather is from the top of that well.

Check your sparkplug.
How long has it been sitting?

idle jet probably gummed up, add a little seafoam to the tank or take it apart and clean it.  That should take care of the idle pops.
Other than that, check the other electrical connections and hope for the best.

Oil level !
I never read anywhere that the oil level had been checked and was w/in tolerance.
Just because you did not add oil, doesn't mean that the crankcase was not too full,....from fuel draining in, etc.

Otherwise, it was most likely compression getting into the crankcase, one way or tother.

The oil level was good, I rode several hundred miles since the last oil change with no problems. When I opened the motor everything appeared to be in good shape, wire mesh was there in the correct place. Is there some way for a significant amount of fuel to make its way into the crankcase? That would be the only thing I could think of raising the oil level enough.

symptoms leading up to the oily mess could have resulted from a failing petcock. I have installed a raptor so if that was the case I should have it fixed.

Alrighty,...  Not burning oil,... so,... instead of finding the cause, let's fix the problem...
I'd try screwing some copper kitchen scrubber material into the breather hose, near the head end... that will do the same thing as the steel mesh in the head, but more... oil mist should gather on it, and drip back down... leave some room for breathing...
Worth a shot?... ...