<HTML> You don't have a choke and I don't know how an air horn would get out of round.
The Spree uses a device called an "Auto Bystarter". This is an electrically controlled jet needle that is normally open when the engine is cold and there is no ignition current being sent to it. Once the engine starts and warms up the needle closes the jet, which has a very small passsage that could be clogged. I had the same problem and had one cleaned out at the Honda dealer as they have the proper passage cleaning wires. You should first make sure there is power at the Auto Bystarter when the engine is running, then check the AB for a resistance value as indicated in the service manual.
The procedure is explained in the service manual and you need to have a digital multimeter to check the resistance.