okay so i changed the oil on my 99 wr 400, I used motorex 10-50, I drained the engine then i drained the frame. I put in the new filter, then i refilled the frame. I rode from my buddys house to mine, ( 1/4 of a mile.) And checked the oil again, there was no oil on the dipstick, and since i used all my motorex 10-50 i decided to put in a little castrol 10-40 i had lying around. I have not started the engine since because i think i made a boo boo. I am thinking about just draining all the oil again and starting out fresh, how much oil do you put in the bike?? Do you add oil through the frame? i also had problems with getting the right amount of oil in the bike, when the motor is cold i was able to get my oil to the hash mark on the dipstick, but when i start and warm up the bike it smokes a little when you blip the throttle, and once it warms up the oil is way over full on the dipstick. Do you check it hot or cold?? Any help would be greatly appreciated as this is my first yamaha.