Hey, i have been on a few of these trails on my dirtbike and have not had a problem with the rangers.. I would say a spark arrestor is a safe bet though even though i never had one.. I have had rangers stop and ask me for the proper info on ATV's though.. But still i would just call one of the numbers in the contact area to be 100% sure..
This is the law for registration. And i believe here in PA you can't insure a dirtbike so this most likely is just for ATV's..
* Class 1 ATV - A motorized off-highway vehicle, which travels on three or more inflatable tires and has a maximum width of 50 inches and a maximum dry weight of 800 pounds.
* Class 2 ATV - A motorized off-highway vehicle, which travels on three or more inflatable tires and has a width which exceeds 50 inches or a dry weight which exceeds 800 pounds