I have a 2006 cbr 600

when you start the bike, all the lights are supposed to go on for a few seconds and the mph count down from 180 to 0. This only happens sometimes for me. Sometimes i turn it the jey on and everything lights up and it is already at 0. It does not count down. Sometimes it also has the red oil light on with a buzzing sound for about 10 seconds then it goes away. After i start all lights are off and nothing is wrong at all. No lights or anything. Is this normal, the light and buzzing along with sometimes not going from 180 to 0.