What are you buying the same bikes as me?
The jetting will be real rich on the 99 KX144 over the entire powerband. I leaned it out to 152 during the summer if I remember correctly and a 155 during the winter. Went leaner on the bottom also. That bike was a nightmare to jet. The needle was different also. I don't remember the exact needle, but I know it was leaner. I raced the bike at sea levelback in Nww York So that should help.
As for the 2002 CR250 leave your jetting alone. The only thing I did was go to the S-8 nozzle. I remember you had a lot of problems jetting your bike with the stumble off the bottom. I would not touch a thing unless you go to Oxygenated Race Gas, Then you might have to go richer. With EG powerband you might find a little goop at first, but that is probably cause you aren't getting on the pipe as hard, mine cleared right up as I got used to have a lot more bottom.
Erik