Advice for going looooong (Double Century Rookie)

[jcs7282]

Looking for any advice, experiences, cautionary tales, tips, tricks, et cetera related to going on a loooong ride – say 200mi +.

Earlier in the summer a friend planted the idea of doing a small group double century around the time of the solstice. For various reasons that never happened, but, I have not been able to shake the idea of doing a double century ever since. I have the opportunity to ride ~100mi to the start of an upcoming event, where I’d join some friends there for another ~100mi. I think I could do it but the prospect of doing it is daunting.

A bit about me and this idea FWIW:
-I have ridden 100-110mi multiple times this season, including routes with significant climbing (8-11k feet) so have no concerns with a “regular” century
-Longest ride ever was B2VT last year (149 mi, 9k feet)
-If I did this I would be riding overnight to the early morning start (no sleep, few if any stores open…would self-support)
-Weather is looking good, dry and not too hot during the day

Main concerns are the whole riding overnight part and just the whole mental challenge of riding through ~7 hours of darkness…only to ride another 100! But I would be riding with friends on the back half, which I think would help mentally.

Anyway, if you have any experiences/tales/advice to share about doing something like this, I appreciate your wisdom!