My 1991 250 will idle around 6k with full choke at cold startup. I usually start around 3/4 choke, which is around 4k and immediately lower the choke until the idle is around 2500 or so. Anything less than that and the bike wants to stumble and try to stall. Once it warms up, my bike idles between 1700 - 2000. I know it's a little high, but the bike seems happy at that idle speed.
Kris