OK, so I got my bike running about a month ago and it ran strong for a couple weeks. It sat for about a week and when i started it up again it started just fine. About 5 mins after riding off, it died, as if it wasnt getting fuel. It would have trouble starting if i tried to right away. If i waited 15 mins or so it would start right up. This persisted for a few days. two days ago (this is where it gets wild) i started it up, rode it around the block and then parked it and let it run. About a minute later a mixture of gas and oil started POURING out of what seemed to be the bottom of the engine. I took off the tank and air filter and started it up again. it ran strong for a second and then the same mixture started spewing from the tube that connects to the air filter! Im talking, EVERYWHERE. A geyser of gas and oil. I have no idea where to start the troubleshooting process on this one. Anyone have any ideas?

 

Is your oil full of gas? I would suspect a failing petcock that's allowing fuel to flow when the bike's off.

 

check your fuel line connections and make sure you didn't hook up to the breather line. Also if you have a bike with an emission control system make sure that it working properly.

 

First thing id do is check to see if there was gas in your oil, Then if there is drain your oil out asap.

Next figure out what caused it, like kilgoretrout said check to make sure your petcock is working correctly. If not replace it.

Check and report back.

 

Not good! Drain the oil, replace your air filter (most likely contaminated with oil residue), refill with fresh oil, run the engine for a few minutes, drain again and refill. Sounds like fuel has washed down into the crank case! BAD but the most likely cause has already been pointed out, and as long as you didn't run the bike for a long distance, your bearings and seals should also be fine.

 

It's also possible you may have overfilled the bike with oil, although what everyone else is saying is probably more likely. A float probably stuck, flooding the bowl, and flooding inwards to the motor.

Drain the oil, change the filter and oil, remove air filter and inspect, it may be coated in oil and require replacing. Clean airbox. Remove carbs, treat and inspect. Attach a fuel lin with fuel in it BEFORE placing on the bike and see if it floods out. Let it sit for a day perhaps and see what happens.