You can ride your bike on the main trails. Signs are posted. Just have to be aware of hikers, and signal early with calling out or a bell. I see plenty of people bike there.
There are plenty of suitable bike trails. Signage makes it clear where bikes are not permitted.
I believe you can ride your bike on all the bigger (main) trails. The trails where you can't ride your bike have a sign saying you can't. There is no cost.
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