not stupid at all .if its the first time u owned an ace and used with out the manual its a good question,behind the right foot peg below the crackcase filler it the dipstick, run engine untill warm (i.e ride bike for 10 mins should do it) let the bike set for 2-3 mins for oil to settle down old bike leave (not) on kick stand, unscrew dip stick wipe clean and put back in engine , do not screw it back in and check oil level there is an upper limit and lower in between the two is fine if level is in normal range just thread it back in funger tight and ride on. i myslef use mobile 1 mtx oil made for motor cycle with wet clutches 20w50 i have 98,000 on my bike no leaks no oil burning and working on 200,000 enjoy