I got a TTR 250 and rode it a while with out the drain plug in for about 20 minutes untill it died.(not on purpose)
Weaks later I filled it back up with oil started it then changed the oil again.
I don't know if shes gonna make it . It runs better with the choke on a little and i noticed the exaust coming rite out of the motor gets blistering red hot even in day light. It looks like its gonna melt right in front of me so i shut it off.

Any help for this is apreciated.

 

friction

 

Running way lean will do that too.Check your spark plug, and jetting.