I've done the slickrock loop in as little as 90 minutes but I'm no longer in that kind of shape. The sign at the trailhead says to plan 4 hours to complete the loop.
If you have a light you could ride after a trail run but do not do a trail like slickrock in the dark.
Playground trails like Bartlet Slickrock that you can hit and spend as much or little time as you wish.
There are trails you could ride from camp but in an interest of time probably would not want to. I'd probably choose to ride or wheel on any given day to get the most enjoyment out of your trip.
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"80 series, with a fridge"
1976 FJ40, Project with little progress.
2004 Starcraft 10RT