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I have a 2010 BMW F800ST and I have a lot of gas in my oil. I have changed my oil and after a day or so the oil will become over filled will gas. I also have ran the bike after changing the oil again and within an hour you can notice the gas in the oil. I have no idea what is going on. Any advice will be greatly appreciated!
 

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First of all, don't run the engine with gas-contaminated oil. You can cause very expensive engine damage that way.

What confuses me here is that I believe this is a fuel-injected engine, so there shouldn't be a direct link from the fuel tank to the engine besides the fuel injectors themselves. The gas pressure is provided by a fuel pump, which is not running unless it is powered up.

I would think if an injector is stuck open enough to flood the crankcase with fuel, the motorcycle wouldn't even run due to a too-rich mixture.

Ok, I'm stumped.
 

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I only ran the bike after I changed the oil, but when I did run it after the change it ran great. Also it is a fuel-injected engine. It honestly makes no sense at all why it is doing this.
 

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Stuck injector or a bad injector seal...that is the only way gas gets into the cylinders...you are sure it's gasoline and not (if so equipped) transmission or cooling fluid.

 

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how can gas get into the crank case?

There is only one way that gas can get into the crank case.

Blown head gasket.

unless you have a fuel stream directly into the cylinder(like fuel injection) then you will have to blame it on a bad injector... hey, replace them all, cause trying to find out which one is leaking will be like hit and miss.

then after you get the gas back in the crank case, change the head gasket!
 
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