This was a late afternoon ride. It was warmer than doing a morning ride. The temp. was 30 with a wind chill of 20 and 15 mph head winds. It took me about 4 miles to warm up, my left knee and back hurt from the start to finish my right knee started to hurt 16 miles into the ride to the finish. It actually started to hurt more than the left knee. Other than those issues I felt pretty good, it was an enjoyable ride, the only thing that could have made it better would a riding partner. About 8 miles into the ride the voice came to me to possibly change the route. So where I was going to go I would have been at a place of no return and in the back roads with very little traffic. At the turn off I decide to go a different route which would give me plenty of options. I was still going to go the full distance but could cut it short if needed too. Glad I made the choice. The batteries for the lights didn't last very long before shutting off, I had back up light and a back up set of batteries for the back up light which got me home by cutting the ride short. With one mile to go, I got a flat and was able to make it home on the flat. I would have froze fixing the tire and no light. My plan was to get home and finish the ride indoors on the rollers.