I am having an issue with the rear tire on my GS Adventure. The tire, a newly mounted Heidenau ( tubeless) will not hold pressure when I run at interstate speed for an hour or so, it completely loses all pressure. The bike can sit and hold 40 lbs for 5 days or I can drop the pressure to 30lbs , ride dirt all day and no drop in pressure. I ran the pressure up to 40lbs , sprayed windew on valve stem, around the rims and no bubbles. This senario has happened two times within the the last 3 weeks. Could the problem be related to when the tire heats up, at this point I am just guessing. Thoughts will be appreciated. Thanks !!!!!