Useful advice will be along shortly, I've no doubt, but as a temporary measure, I would standardise the comp and rebound settings per the manual, front and back, then up the pre-load (from standard) at the back by a bit.
I'm 6' tall, and near to your weight, and I find upping front & back comp by one click each from standard works for me.
Someone will be along with information and a link or two to more detailed advice.
The only time I feel I'm going off the back of my 999S Bip is on the Mountain at Cadwell!
