Search on "fork seal cleaner". It's a little thingy that pulls the dirt out of your fork seals without having to disassemble them. You might just have some dirt in the seals.
Seal Mate. The local non-BMW powersports dealer has them or you can get them online from various places (I'd use ebay). Most fork seals aren't bad, they just have dirt and dust and bug guts in them. Seal Mate helps to pick that stuff out. My fork seals were leaking a while back and replacement of the seals wasn't necessary. I just used the Seal Mate then changed my fork oil.