outashape

I think you will do fine. I would take the lighter bike. I am female and about 50 pounds overweight. I have twice cycled 4 centures back to back in the rolling hills of northern Michigan (DALMAC). I have cycled on Pedal to the Peaks where there were days of over 100 miles (but not back to back) with a total week of 30,000 feet of climbing. I have cycled on the side of interstates (not scary, truckers give you plenty of room, just the noise level and debris are problems). I have had a year where my total mileage was around 8000 miles. If the 6 hour century is not including breaks and will be adjusted for the days that are in the mountains, it shouldn't be a problem if you usually cycle around 16-20 mph. I have found that the first day is easy, and then either day 2 or 3 is rough, after that each day becomes a little bit easier. If the tour is supported, it will take the worry and pressure off of you. If you have any type of recurring health problem, etc... tendonitis, sore knee, etc, it will become worse each day. Another thing, I found going down hill in the mountains to be exhausting mostly due to the concentration level. If you have a 10-20 mile down hill,come to a complete stop every 5 miles and rest for a couple of minutes. I did find my pectoral muscules (which I never knew I had) to be sore after a couple of downhills. On hills around Michigan, I can reach speeds of 45 mph for distances of under 1 mile. In the mountains, I try to keep my speed to 30-35 mph so I don't go out of control. The weather is usually cooler at the top of the mountain, so the rims don't overheat up there, but you are usually "cold". I think it sounds exciting, write and tell us how it went.