I have just brought a 2005 gas gas 250cc so my knowledge of engine's is rubish the problem i have is doing a oil change i know where you drain the old oil and i know where you top the oil up i just dont know how much oil to put in or where the dipstick is???

loads of info on this in the forums mate, but here goes for you. 400cc or 400 ml of atf dexron iid, or light gear oil . once you have put the oil in then with the bike stood upright if you look in the sight glass on the clutch cover, it should be about 3/4 of the way up the sight glass.

I tend to use 450cc. ATF is fine. No dipstick, use the sight glass.