Checking the oil on the CS will often result in overfilling the bike!
You will have to check the engine oil after you have done an oil change! The engine oil checking procedure is as followed:
Run the bike so it is warm: Ride the bike! Did I mention that you really need to RIDE THE BIKE?!?! Like ride for 20mins or more! The oil has to be warm inside the frame, not inside the engine. You are measuring the oil level in the frame. With the frame being cold the engine oil will be cold and your reading will be inaccurate!
Park the bike but let the engine idle for ONE MINUTE to see if the fan comes on. If the fan doesnt run yet, let the bike idle until the fan comes on.
Turn the bike off and wait an additional minute.
Now get a clean white towel and place the bike vertical, unscrew the oil dipstick and wipe it off.
Take the wiped off dipstick and sit it on the top of the threads without screwing the dipstick back in.
Remove the dipstick and immediately place it onto the white towel: Based on the impression on the towel you should be able to see what the oil level is!
The oil level needs to be in between the MIN and the middle mark NOT MIN AND MAX
Oil level to be in between || and Min!!!
If you think that you need to add oil, its probably high already. Check your oil level again after a ride. I never had to add oil to the CS at all. Heck, even with 2,4L it was overfilled sometimes