If your forks are to soft or maybe not rebounding correctly follow these steps.
1. Check the spacers in the wheel to ensure there are no gaps and/or the speedo drive is not positioned in correctly. This may cause undue friction on the fork legs and result in the forks sticking slightly.
2. Ensure the fork seals are not leaking (replacing fork seals is usually a job for a mechanic)
3. Add Fork oil to the internals of your forks: This is the most common and easiest procedure. You can do it yourself.
- Remove the cap from top of forks with the correct sized spanner (Depends on year model so we won't quote what spanner size)
- You can add 30ml each side to begin to see if it makes a different.
If this is not enough, You can pull the front wheel out, then drain the fork oil and replace the total fork oil on each side.
Below is a post from Nicholas G which is worth reading if working on your ST250 at home.