There are signs forbidding bikes.
I agree with Chelsey. Its mainly a hiking trail not really suited for biking. But there were no signs that I saw that prohibited it. I too would not recommend biking it.
There is a series of three gates coming off Hwy 79 for the first half mile that require you to step over a raised bar, this is to prevent livestock from escaping but also dissuades bikers. It is not impossible to bike to Eagle rock, but this is a hikers trail, a heavily trafficked hikers trail. I'm not sure of the rules of biking this portion of the PCT but I would not recommend biking.
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