This so called sticky feel is normal for new flatwounds. As I don't like this as well, I always prepare a new set of flatwounds before I put them on the bass. I give them an extra polish with very fine Scotch Brite abrassive pads (the grey ones). After having done so, I clean them thoroughly with alcohol. This makes them very smooth, not being sticky anymore.
Just a cover of a real bassist
Beaten and beaten up by time