My dad just bought a 06 500 and twice it has tried to fill the crankcase with fuel. I pulled the carb put a new shindy kit in it. It was fine for the first 5 miles then it did it again so I pulled the filter it was clean so back to the carb. I pulled it cleaned it again, even though I don't see anything. I put a hose on the fuel inlet and blew through it and moved the float to make sure it was shutting and it was. Put it all back together. And it was good for a couple of days and right back to it. When it goes it is pooring gas from the carb and the vent tube. I am wondering if my pump is pumping to much. Could that be an issue? Could I put a in line regular to help or should I just get a new pump?

 

Bst 40 carb float level setting is critical. Have to have it right or it will leak or like yours fill the crank case. Some even set right will have a slight leak at the overflow. Here's a good breakdown on the carb used on a ktm.Look at the bootm of the post and shows how to set it right.The BST-40 Bible - ADVrider Plus here's a pdf fuel section on carbs from the service manual.https://www.google.com/url?sa=t&rct=...,d.aWw&cad=rja