This one is pretty easy, about 3 hours round-trip hike.
Walk up to Flynn Road, at the cul-de-sac start walking up and to the right on the gravel road.
You'll take a left up the obvious trail in 50 yards or so. Just keep following the trail all the way to Bear Valley Ski Area.
The trail exits in parking lot for buses right behind Koala Chair. I heard you can continue onwards along the ski area ridge and get onto another trail which takes you back to town along Bloods Ridge. That would be another 2-3 hour walk I suspect.
You can take a mountain bike on this trail, or even a 4WD or dirt bike. The road does show up on the National Forest maps as a Forest Service road, so it is open for public access. I took my 525 KTM through that trail recently and I got to the ski area from Flynn Road in about 15 minutes.
