Its the same thing on my 2004 wr450f. The bolts thread was worn right down and did not tighten. Before i tried tapping a new thread i tried a new bolt and it fixed the problem and i was able to get the correct torque. so check that the bolt is also not worn right down, I've yet to ask is this point just a drain hole for the filter or does it need to be there for oil to get pumped around?? Because before i got the OEM part i tried it with a normal bolt with the same thread and it tightend. so was relieved i did not need to tap the hole. I've found alot of the bolts on the yammy are very soft and feel like they would easily thread themselves.