Do you mean a too stiff spring or too much compression damping? Or a combination of both?
What is your sag with you on the bike?
If it's less than 1/4 of your total travel or 1" or so, the spring rate is probably too high.
You could try a CB400F spring. Also, CB750f springs are softer than K springs, in my experience.
Or call racetech or wp and order one to your specs for $120 shipped or so.
If your sag is about right, then you probably have an issue with compression damping.
In that case, start drilling the compression (lower) holes in the damping rod. Just go gonzo and drill them out to .250 each if you're handy with a brazing rod to fill them back in if you go too far. You don't have to do both forks the same, btw.
OR, if you've got lots of cash, get a Racetech valve and forget it.
What weight fork oil are you running. I remember AD having this problem on his 175 when he used the really heavy stuff.
Rather than play the fluid hokey pokey, fill your forks up with the stock fluid or something slightly heavier and then install a schrader valve in each of your caps and use air to dial the forks in to the track conditions (unless air shocks are not allowed in your class).