this is strange but my bike starts right up when cold, even in 40 degree weather, but when it's at running temp it's often hard to start.. why would this be? Something to do with a leaky hose or gasket in the fuel system? it's a 2003 carbureted Dyna and is under warranty.. I always leave the fuel valve on reserve.

 

Have you tried cracking the throttle open just a bit, while cranking?
May help.

 

You may want to leave fuel valve in the ON position, if its left on reserve and you run out of gas you will really be out of gas and have no reserve to get to a station


As for the hard start, trying giving it a shot of throttle prior to starting

 

Leave fuel valve on ON. No reason to run it elsewhere.

Sometimes carbureted bikes, or anything else, will act that way. Just crack the throttle a bit to give it a squirt of fuel and fire up. It's normal for them to act that when they are shut down hot. There is no fuel boost to get them started when they are hot and no choke is used. The hot engine trying to start on idle fuel just doesn't work well, but sometimes you get lucky and it will fire off.

So yea....crank the throttle one time and hit the fire button. Should cure your problem

 

+1 on crank the throttle once.....had a Sporty did the same when hot