I heard about the trails built @ Raystown Lake.
What about technical riding near Lewistown?
Go west...Roth Rock and Bald Eagle State Forest have lotso options 20 minutes drive from Lewistown
Coopers Gap in Rothrock is very close to Lewistown.
Salsa El Mariachi SS
Check out IMBA' s MTB project and you will find maps for the best trails in Rothrock. You can also get the purple lizard map.