There has been people having this problem, check you vent line for your tank.
It is under the cap, if it gets clogged causes a vacume in the tank and wont let fuel flow out.
In the morning the motor is heating the tank and creating pressure, once it is hot from sitting in the sun cant get any hotter, when you ride the wind cools the tank creating a vacume.
Take a straw and try blowing through the line, may also be pintched under the seat.
Chad Falstad "Hawk"
2011 HD Ultra Classic "angel"
2001 Nomad 1500 Sold March 2012
2001 VN 750 "Sold June with 2008 with 21,000""Serinity"