Adam from KC on 4/16/2019 12:13:54 PM:
Hi, I recently rode the Rock Island Spur that you're referencing and it was fine. It is short on amenities in that water is tough to come by, but there's a little local shop near a trailhead in Chillhowee called The Country Store that will fill up bottles for you provided they're open.
Otherwise it's pretty easy and open, if not a bit washed out in small areas. Careful of larger rocks as my front wheel met one last summer and I wiped out!