This was a layover day at Happy Camp with an optional ride to Gray Mountain and back. Basically a long hill climb and the sun with no breeze was dead on to my face. Really really hot. Heat exhaustion biker at the turn around needed a lot of help. Last 2 miles to the turn around were 2 steep 10%+ hills that were brutal in the hot sun. On the fun side, the turn around had butterflies everywhere and were suppose to land on you if you put something sweet on your arm or nose. Apparently, they did not like the sweat on my nose. Data: Day 1 of 71 miles and used my battery at L1 for most of the ride. L2 for many 10-15 minutes. Still had main batter(24%) when I got back. Day 2. Climb out of Happy Camp, the bike in L! really felt heavy and sluggy. Went to L2 and stayed until mile 11 and main battery was only 20%. Went to Range Extender to finish the ascent. Learned that at L2, the main battery draws more power than the RE can refill/recharge. Consequently you cannot get the assist expected at L2. Lesson learned. Ended the ride with RE at 0% and main recharged to 69%