Forks on the sport are waaayyy too soft as standard (unless you're a 30kg frenzied monkey). I have yet to refurb mine (or even check they're straight.....

) but you should look at stiffer springs/heavier oil as a minimum.
The only springs I've found so far require the fork tops to be machined (not sure how) so I'm still looking for an easier solution. Let me know how you get on.
Cheers,
Ali
ps: Race Committee, can we please, please have adjustable forks one day? It's a right pain trying to find one setup that'll last the season....