Originally Posted by ciedema
Punch it don't drill it. That said the metal form the end is softer than the bearings so it won't destroy a bearing. The bigger problem would be blocking one of those oil jets in the motor.
Softer,,, really??? Unless KTM uses some sort of different bearing material than everyone else, bearings are three layers. The steel shell, a soft aluminum base and a softer aluminum plating. Once the plated bearing surface gets damaged it doesn't take much more to wear down the base aluminum. That soft chip of tin from the end plate of the filter will do one of three things: pass through the oil gallery and embed into the bearing and not be an issue for the most part. Pass through the oil gallery and be spun around the bearing, scoring the surface with every revolution. Or make it some other point in the engine; maybe a good spot or maybe not.
I wouldn't take the chance. I have dealt with bearing issues in bike engines and marine engines for going on 40 years.