It appears that a piece of foreign material is stuck in the upper couple threads where the oil drain bolt screws in on my '00 CR250.
The bolt is a 12mm diameter but I'm not sure of the threads per mm. I measure about 1.5 threads per mm but I don't want to use a tap in the hole until I make sure I have the correct one.
If you take your fastener to a machine shop or a auto shop they should have a thread pitch gauge you can measure the thread pitch with.
I would suggest using a forn tap to chase the threads as it will not make chips as it forms instead of cuts the threads.
I always use forms taps when rebuilding my motors makes for a very tidy job.
I was able to find a person with a metric pitch gauge and it is 12x1.5mm.
Called around and found the tap at a NAPA auto parts store.
SFO - Your right - I don't need to cut new threads, just "chase" the old ones.
Sometimes using a LOT of grease on the tap also helps catch any chips that may come off.