Busa cranks real slow when bike temps gets high


I have a 2004 busa with 10,000 miles ,the bike starts fine when it i start it up when the temp is cool,but when i am sitting in traffic for a while and when i finally get parked and turn the bike off , when i try to start the bike back up the starter drags real bad.the battery is about a year old ,but is fully charged.the only time it drags about starting is when the bike temp goes up and stays up for a while.i always charge the battery up in the winter, i have never disconnected the battery when i charged it up,i was told that i may have damaged my rectifier /regulator by not taking the wires off the battery before i charged it. I would appreciate any advice.
have you had any work done to the engine. a higher comp engine will do that with a stock battery. your battery could need replacing too.

welcome to the org.
Hot copper has higher resistance than cold copper so it takes more power to turn the started when everything is hot.