+1 to the above... Also, when you change the filter and refill the crankcase I recommend you fill to the center of the oil window - DON'T FORGET TO PUT THE DRAIN PLUG AND FILLER CAP BACK ON - (and don't ask me why I say that..
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Start the engine and let it warm up - the lower case should be warm to the touch - and shut things off. After about 10 minutes recheck the oil level... you'll likely need to add some. I bring the oil level
on the centerstand to the middle of the window. The manual sez to check it on both wheels whilst sitting on the bike - a real chore for me. I have found the oil level will read slightly higher in the window on both wheels compared to on the centerstand so this makes it easy and reduces your chance of overfilling.
It's a lot easier to add oil than to reduce the level so once again.. take your time and enjoy the fact you know it was done properly.