Great weather today. I bit cold and mild winds. I wasn't sure which direction it was going at first. The legs felt reasonably good from the start. I was sufficiently warmed up by the time I reached the end of OTR. When I got there, I was feeling a bit hungry. So, I told myself to wait till I reach the summit. As I approached the summit, I still felt hungry. So, I pulled over and ate 2/3 of my Power Bar. Shortly after, I headed to WS. The wind continued to be mild and was traveling West. So, I had a slight headwind on the outbound. When I reached the turn-around point, I pulled over, replaced the battery on the GoPro and ate the remainder of my Power Bar. The return trip was quick. I had a mild tailwind at this point. I made my way back to OTR and the rest was mostly fun and games. Concentration was very good. I had a few things to think about. No gremlins. Balance and form felt good. Ailments, next to none. Gear is working great. Although the GoPro showed an error on the SD card when I swapped the batteries out, at the turn-around. I re-seated the card and that did the trick. Other notes, I saw a couple on a tandem. Once at the end of Country Club, and again, when I was on my way back from WS. Always good to see fun stuff like that. I also saw one casual cyclist on Highline, and another as I was making my way back up Mariposa. I spotted some gliders near WS.