Have you had the suspension rebuilt, or is it the same stuff fitted 16+ years ago? If it is, you really really ought to spend the cash and have it done.

Assuming it is, then maxing the pre-load is surely going to make the chatter worse, as the suspension is so hard it can't follow the track surface properly.

I'd have thought softening the pre-load and upping the damping would be the right way to go.
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