hi chillo i had the same problem on mine when it was new so i fitted the rear spring from the 999s bp and the difference on hi speed long corners was amazing (i weigh 96kg if that helps.....)
i've moved the seat forward as far as possible which has helped a little. But it turns like a bus still, going to dial in some more rear ride height and possible a bit of rear comp.
hi dave. ive got a front from my 996 from dymag (full carbon) and fitted it to the 999 with the discs from a 99#r the difference was amazing after the bike had been a bit better set up, stonger spring on the rear and more ride hight one problem i incountered with the carbon rims is thst the tyres have a habbit of turning on the rim under heavy braking.... thus spinning out of balance, realy annoying evry 20 sesion re-balancing tyres..
Only had that problem with the rear spinning up on the rim..... what a pain !!...... I put a dot on the tyre now..... when you next change your tyres try fitting them up dry..... works for me .
2 full turns of ride height has made a big improvement. I don't plan on changing the rims as they are the black forged type, 57mm system + PC3usb will be going on first.
still getting a little bit of movement at high speed (130+) when cranking it over, could be the aerodynamics