I'm working with the information that I've gained over my summer long rides and the Chesapeakeman Aqua Velo experience to fine-tune the foods that I take with me on the bike at Ironman Florida. I know I'll need somewhere in the range of 300 calories or more per hour for 7 hours, which equals 2100+ total calories. I have a short time-tested list of solid foods that agree with my stomach, that are easy to pack along, and that I can nibble on while riding fairly readily. Fortunately my stomach seems able to tolerate solid food reasonably well unless it's taken by surprise, or it's a record-breaking heat wave (over 85*F) on the bike course.
I think it was Linae that gave me the idea of plugging it all into Fitday to make sure the amounts and calories and nutrient ratios came out right. It's been interesting to tweak the amounts a little to fine-tune exactly what to bring on board.
I wish the process was this exact out on the bike course, but there are always some foods that just look too dry or too gross to eat once you start getting tired or overheated. I think I'm down to a few that have proven to work well for me, though.