Not to sound like a broken record here, but I had a similar experience. Out riding the roads on my mountain bike near McCausland on a Sunday morning when the big road ride from Dubuque to the Quad Cities was going on. I was going the opposite direction. Every rider I passed I gave a hearty Good Morning to and a/or wave. I'd say about 75% percent gave no response at all! I will say this - most, if not all of the women riders did give a hello back. So is it just the dudes? At some point I turned around to head home going with the Dubuque rider traffic - got passed by some hardcore roadies and appreciated how fast they were going - I said "Way to go guys! How many miles ya' got in so far?" Absolutely no response and they were riding six inches from my left side as they passed. Maybe I was violating some rule of etiquette by even asking a question. On the brighter side, later in the morning a storm blew up and one of the road riders and I decided to take shelter in a ditch and he turned out to be a very nice fellow. I don't know if not acknowledging a wave or hello makes you an a-hole but I just don't get it! So as someone else said in this post, there are jerks everywhere - even on mountain bike trails, but dang, there sure seem to be a lot of them who ride road bikes! I will continue to greet any fellow rider I encounter out on the bike - on or off road. Maybe I'm the dork for even contemplating this subject. ;<)