Did a solo ride counter-clockwise around this loop on Sunday, took just over 2 hours. I was glad that I got a relatively early start, as much of the road is south facing and pretty exposed to the sun. Riding the lolipop clockwise would let you do most of the climb in the shade, and the road grades seemed pretty similar. The "collapsed bridge" mentioned in the description has been replaced, this ride is 2% paved, 98% logging road and zero single track. I was glad to have downloaded the gpx track, as there are a lot of road forks to get lost on.
There are some great views, especially of Mt. Rainier, but mostly on the way up; at the actual summit near the antennas, there are too many trees to see much of anything! Best thing about the ride was having the entire thing to myself - except for the three sketchy dudes who came walking up the road from Hwy. 18 and disappeared down a well-beaten path into the woods near the trailhead, I didn't see a soul the whole ride.
I rode it on a CX bike expecting an aerobic gravel grind; in fact, most of this ride is very steep with lots of loose rip-rap on the road surface. With 36x27 as my smallest gear, I found long sections to be barely rideable (only had to walk two short sections, but it was a near-run thing). Next time, I'll take my MTB, spinning up the climbs and blowing down the descent would be more fun and probably faster.