My wife and I went for a bike ride along the canal path. She on her mountain bike, me on my new homebuilt cyclocross bike. The first part was paved, but that gave way to a dirt path covered with fine gravel/sand. I opened the bike up, and had it up to 27mph on the dirt path. The path is relatively flat and level, and I had a slight tail wind. On the way back I had it up to 26mph on the pavement into the slight head wind. I was in high gear both times I got the speed up. I could have probably had it going faster is I have a bigger ring on the front. But the lower gearing is fine for what I will be doing with the bike.
While riding with my wfie, I had to consciously slow down as it was too easy to pull away from her, much more easy than on my mountain bike.
It was comfortable to ride. I really wasn’t aware of the biopace rings, other than when shifting. I will have to get used to the bar end friction shifters since my other bikes all have indexed shifting.
I will have to take the bike to the actual off-road duathlon race course sometime and see how it does. I think it will shave at least 5-10 minutes off my time for the 10 mile course. I don’t know.