87 spree carb issues

[vcvracing]

trying to get a 87 Honda spree running for a guy at work I can get it to start when it is cold it will run for about a 90 secs and then wants to go full throttle what could it be I have cleaned and assembled the carb 6 times now have free flowing jets all of them, a new by starter new petcock. I am not sure what would cause the bike to go wide open after it gets warm.