I have a 2004 WR 450F with a SFB oversize clutch cover. I am having a hard time figuring out how much oil to put in the bike after an oil change. Stock is 1.1 liters or 1100 cc. With the oversize clutch cover I start out with 1250 cc, but sometimes I get clutch slippage. If I add a little mover 25-50 the clutch seems to work better. I was wondering if anyone else uses the same cover and advise their experience.