any help with this one!!!

hi, all

i have a problem you might be able to help me with??

i have a yzf750r on a 93, if i have been out and the bike is red hot,

when i turn the engine off and try to start it up stright away it feels like the battery is flat and it

wont start but if i leave it to cool down for a bit it fires up first time everytime!!!

anyone got any ideas????

any help will be good

thanks