That is a nice ride. PA125 north out of Pine Grove is a good Sportbike road, the ST does fine on the twisties as well. From there, there are a variety of very good roads and direction choices. I live about 15 minutes west of the north end of 125. You can cut across and take 147/225 back to 81 by Harrisburg and ride 81/78 east, or take old 22 instead.
From the Exit on I81 at the Cracker Barrel/mall, you can pick up PA339 north and there's some old Reading Lines roadbed I've ridden my WR on in the past, really nice country if you know your way around. It is about 45 minutes east of me.
A really good ride from there would be north on PA42 up to Eagles Mere, then on to Worlds End State park.
Much of these areas can be viewed on my Photobucket account, under the same screen name as here. The old rr grade is also considered the Catawissa RR grade, the rest are self explanatory.
A coworker just took delivery of a new Tiger800, we plan on spending most of the weekend on the road. What's the point of having a new bike if it sits in the garage.