91 RM250 used and abused

If the wheel bearings don't turn freely, then you're probably going to need to replace them. About $15 for the rear and $8 for the front.

You need to set the suspension sag for your weight. Then adjust compression and rebound clickers to get the ride and handling you want. Lots of tutorials on how to do this around, just use the search function here. May even need different rate springs for your weight.

Remove/check the swingarm bolt and grease it.

If you ever decide you'd like to replace the stock pipe, let me know, as I have a new, never installed FMF Fatty nickle plated pipe to fit your bike that I'll let go for $60 + shipping.