Eric…
“I typically drank almost three bottles between each check stop (except only 1 1/2 to the first check).  I had one just water and two with either Accelerade (works good for me) or the Gatorade mix that was supplied at the stops (1 large scoop per bottle).  For these long rides I have found that you must take in solid food.  I try to each an energy bar every hour.  The Luna bars work great- good taste and easy to chew.  Also the pretzels were great to take in salt.  However, a sandwich or soup if available work much better (real food).  John J. gave me a few of his endurolytes in the last hour and it gave me a little needed boast at the end.  Taking in the coke worked well - although the effect runs out quickly- caffiene and sugar jolt. “

John J…
“I had about 80oz. of fairly diluted sustained energy in my Camelback, two 20oz bottles of a choc. energy drink called Enduro Optimizer, two 16oz Cokes (Thank you! I owe you.), someone gave me about 8oz of Powerade, and I probably had four 20oz bottles of your Gatorade mix. For solid food, I had one Luna Bar, one half of a donut, one pretzel, one half pack of those Welch's gummy snacks, one banana and probably five GU's. I also used one or two Endurolyte capsules every hour, and had two Advil during the course of the day. I think that was about it.”

From John Fuoco...
Fluids: generally about one oz per mile will work for cold and moderate temperatures. When its hotter you need 1.5-2 oz/mile. At the Michigan 24hr race where I rode 409 miles I drank 600oz and was still woefully behind. There the temps varied from 95 in the afternoon to only the low 70s at night. At petersham I estimate I drank about 280-300oz and could have used more as evidenced by the fact that I did not need to pee all day.
Calories: Most should be carbohydrate for anything 200 miles or less. A 160lb rider can only absorb about 300cal worth of carbs per hour. Forcing more down will just cause bloating and discomfort. I happen to use sustained energy or perpetuem for most of my calories. I will also suppliment some gels, any brand, to top things off and appease my taste buds. Aside from an erant banana or cracker I do not eat solid foods mostly because my own experience has been that I have less stomach issues this way. For others the opposite (eating lots of calories in solid foods and drinking mostly water) works better. The key is keep the intake of both calories and fluids steady hour by hour. Here again its easier to do this if you are drinking your calories. If you are feeling super the first few hours and take in little or no calories, guess what, you will not be able to make that up later. All you can do when you bonk is slow down. Not a good option
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So….Eric drank about 16.5 bottles or perhaps 330 ounces total….maybe more if the bottles were large.  John J. drank 240 ounces and John F. up to 300 ounces.  Based on the water we had left over from the ride, I estimate they drank at least 100 ounces more than the average Petersham rider.