My bike tries to start but won't, no matter how much choke I give it

It's possibly flooded. Mine floods on a warm day with too much choke, and then turns over but doesn't start. After cranking for a few seconds, it will sometimes sputter just a bit and a bluish-white smoke will come out of the pipe, but still won't start.

Try cranking a couple times in 5 second bursts with no throttle. Then, as you are cranking, hold the start button and simutaneously add choke slowly until it fires (when mine does this, it starts up with maybe 1/2 choke; any more/less and it wont start). Be careful you are not running your starter for more than about 15 seconds at a time or you may damage it.

On warm days I normally crank it for a second or two with no choke and no throttle to clear any raw fuel sitting in there before adding choke (it usually starts with no choke if it's over 70 degrees).

If you are still having problems, you may want to take a closer look at your choke plungers. Make sure they aren't sticking. Also check your float valves to make sure your float bowls aren't overflowing, which may also also flood your engine.

See also: This page has some more ideas for what you can do if you flood your bike.