ok, sorry for not been clear.
basically (in racing use) when i brake "hard" and i downshift 3-4 gears with Woolich blipper, the bike gets into a slide left-right (like snaking).
I strongly believe it can be corrected with a better geometry (less weight transfer towards front) but I also believe that the slipper clutch does not reduce the counter torque enough. Maybe i am wrong, but would be nice if somebody know how to (whether it is possible) modify the clutch to make it work a bit better.
Ubba, my friend, you must go 'after market' for your slipper clutch needs, because you are asking the cheepo Suzuki system to cope with some pretty harsh/unsympathetic down-shifts, and I'm surprised you haven't popped the drive train somewhere.
Try Sigma, but don't expect even them to fully resolve your challenge.