The level for a 2005 CRF250R for the engine is 660ml's without filter change and 690ml's with filter change.
The tranny for the R is 800ml's.
The recommended oils are:
Engine - Pro Honda GN4 or HP4/HP4M
Transmission - Pro Honda HP Transmission Oil, GN4,or HP4 without molybdenum
In truth you can use almost any top quality oil. Take a look at this for some ideas of what others are using:
http://www.crfsonly.com/forum/viewtopic.php?t=13754url
It's for the 450X but you can adjust the volume for your bike.
Joe
'05 CRF450X,McClain suspension, Cycra Probends, Pastrana FMX Pro Tapers,BRP Sub mount & Scotts stabilizer.See carb sticky for more