Weather is a major influence in this area. Do not ride the trails after rain or during muddy conditions.
The Cache Creek Ridge Trail can be accessed from the Judge Davis Trailhead down to Cache Creek. It is not in Wilderness. It is OPEN to bikes. There are trail signs with bikes on them, showing the way. It is doubletrack, rideable, but quite strenuous in spots. The key to this one is the creek at the bottom. If the water is high, you cannot cross over to Route 16. It can be crossed when the water is low but it isn't easy getting up the other side and onto the road because there is a barbed wire fence and a guard rail.
Also, the flow for Cache Creek is not only influenced by rain but also from the water authority on the dam up at Clear Lake. If they release water, Cache Creek might not be able to be crossed.
The County Road 40 crossing at the low water bridge, which is where the Blue Ridge Trail
, Fiske Peak Loop
, and other trails can be accessed, is a cement walkway open to hikers/bikers but is not passable if there is high water. I highly recommend that people check in with the BLM office in Ukiah and the water control/dam authority at Clear Lake.