Track Day Rider
Join Date: Apr 2016
Location: Sydney, Australia
Just be aware that compression can also affect your sag values. Do you know what spring weight is in it atm? 66kg is very light. As long as your fork oil isnt old and abused, then I'd say your springs are too heavy.
As the guys said, have a skilled tech take a look. But if this isn't an option, I'd say your first port of call will definitely be a respring. If you're 66kg and you've got 20mm of sag with preload all the way out, I'd guess you're running something along the lines of .8 to .85 springs.
Ideally you can just get faster and brake harder in which case you'll be riding to the springs anyway. The faster you get, the stiffer the springs will need to be :D