If you have the wheel of the motorbike

Many riders like to race the keirin from the front, you have clear space, can't get boxed in and if you have good speed-endurance, it's not a bad place to be.

Generally, it helps to have the motorbike, if you do, there's a couple of things to be aware of. Firstly, you can't overtake the motorbike until it has left the track.  This is important, as everyone else can overtake you, or be accelerating so that they can.  You can bet that someone, out the back, will take an early flier to try and get past you while you're trapped.  If they time it well, you're still doing the speed of the motorbike and you're a sitting duck, there goes your lead.  Everyone else will have jumped on the wheel and you're out the back.

So, with 3 laps to go (assuming a standard 2.5 laps to go pulloff of the derny) you need to give some distance to the motorbike - yes, let it go a bit!  Inexperienced keirin racers with the derny's wheel are reluctant to do this but it is vital.  Generally the slower the motorbike is going, the more distance you need to give it so you can start to accelerate before the bike swings off the track.  At least two or three bike lengths as you come out of turn 2 gives you room to move. If you're hard on the wheel of the derny, you can't accelerate and you will often get swamped.  By opening a gap, you have room to accelerate and to jump onto the wheel of the early attacker, giving you a free ride for a lap.

Also, when the early move comes, DON'T PANIC!  If someone takes a flyer (kilo riders will often do this, or more endurance-focussed riders) you don't necessarily have to match them, you just want their wheel, so don't jump hard early and blow up, but use the gap you made in front of you to accelerate as smoothly as you can, and get the wheel of the early mover.  They will want the lane, perfect, you're now in second wheel with two laps to go.