Ktm lc4 640 fuel/carb troubles?

i recently purchased a 2002 ktm lc4 640 to use for desert racing . i was going to purchase a honda xr650r (and still might if i can't overcome the carb troubles with the ktm) i race motorcycles off road the pro level and have been doing so for many years (not factory , just local and district ) i have been running an old xr600 (sherman tank) and decided to finally upgrade to some newer technology. ok here it goes, i like the ktm overall, but it has a serious problem. any time i get into any type of rough or choppy sections the bike falls on it's face and will most times want to stall, out or does , like it is running out of fuel. at which time i am almost tossed over the bars from loss of momentum.the bike starts and runs fine as long as the ground is not too rough, but braking bumps , whoops and sharp consecutive right and left corners cause the trouble and in desert racing , this is a major problem. most i have talked to have told me it is a carb float hieght issue. just though i would ask here to get some other input. all is stock so far on the bike, i haven't added any aftermarket performance parts and won't until i get this issue straightened out. any info would help. i know the suggestions of buying an xr650r are coming , but i would rather make this one work before going out and buying another bike. the 640 seems to be a great bike other than this problem. thanx ahead of time.