Our resident shop mechanic is reading this thread over my shoulder.
He says air it up to 65 and let it sit overnight to make sure that the tire seats correctly on the rim. Then back the pressure off to your desired pressure and that should solve the problem. Also check to see that the valve stem is seated properly you may be losing pressure there.
Failing all of that- just use Stans... It works like a charm.

Hope this helps

ciao!
Denise