I have a 1990 ZX6D with a recent starting problem. When the bike is cold it has no problems starting. Upon trying to restart the bike after it has been ridden for a while (engine is warmed up), it will not start. Finally the battery goes dead and I have to push start it. If I shut it off (after push starting it) and restart immediately, it restarts right away. The bike's tendency not to start occurs after it has been sitting for 10-15 minutes, if I wait longer (1 hour or so) it starts no problem. My conclusions are that it may be a faulty starter (perhaps it is draining more power when the bike is warm) or a fuel pump/fuel pump relay (but after looking thru the manual I'm not sure it even has a fuel pump/relay; does it?). Any suggestions would be greatly appreciated.