I have a 99 I/S & a 2000 STD, Owned both for over 30,000 miles and are basically stock,They will both start without the enricheners, but if you touch the throttle they will die, Both need to warm up a minute or two before you can ride away. been that way as long as I've owned them, I have a buddy's 97 Tourer (stock exhaust and air filter) in the same garage at the same temp. You can start this bike with no choke, blip the throttle to any RPM (no stutter or hesitation) and can ride off immediately. What is your best guess as to the difference, Jetting? idle mixture? or just one of those things that make you go HHMMMM?
A cold start (room temperature) requires a slightly rich mixture. If your mixture is correct, and the '97 is slightly rich, you will see this result. Just to be sure, you should go over your vacuum hoses and other areas prone to vacuum leaks.