not 'effing much. there are 2 oil cavities. 1 for trans and 1 for the motor. if u change the filter and the engine oil its like 600cc's just the oil it's 550cc's or so. put in 500cc's and then stick it. i run mine at the highest line on the stick without the stick threaded in.
trans is 600 also.
these things use a bit of oil too. mine has since new with a new piston or 1 with a few hrs on it. check the motor oil regularly. i do at least once a session.
change it every other ride. for me that's like every 4-5 hrs of use. ichange trans oil every other motor oil change.
changing is a bit confusing too. the engine oil drains out of the bottom of the motor on the opposite side of the engine oil filler. thats the 1 with the dipstick.
the trans oil drains out the left side of the motor and all over the frame rail making a nice mess. u check it from a weep hole on the same side as the trans oil filler.
confused? i was. get a manual if u don't have 1.
these are great bikes tho. i have hammered mine and it keeps coming back for more.