I rode the bike course for my race this weekend. (Pac Crest Oly)  The road is crap for 18 miles.  This is a temperary course as there is road construction.  Since I was doing an out and back because I had no other way of getting back to my truck, and only 1 hour 45 to do it, I only went the first 18.2 miles, and then headed back.  took me an hour and 40 minutes, and I averaged 21.8 mph for the ride, which is good considering I did not push at all, the road was crappy, and I had a serious head wind on the return.