Fuel

It is completely individual, and depends on your sweat rate. 

Take a look at this link for information on how to test your sweat rate and determine your hydration needs that way http://www.endurancetriathletes.com/calculating_sweat_rate.pdf

Sweat rate has zero bearing on the amount of fuel an individual needs to consume during endurance sports.  It does have relevance in estimating hydration needs.

For bike rides lasting about 90 minutes or longer, the average athlete functions best by consuming about 150 - 300 calories per hour of mostly simple carbohydrates (some people do best with a some protein and fat along with the carbs too).  It's a big range, but needs can vary significantly from person to person.  A good approach is perform your long rides at a higher intensity than you're going to use on race day, and experiment with different fueling rates and different sources to determine what works best for you.  Larger athletes tend to need more, while smaller athletes need less.  Keep in mind that fueling rates are going to be dictated by how much you can absorb at a given intensity, not how many calories you burn.

Coach Don and Shane have stated it well. 

it you want to read a marketing ad with some information take a look at the Hammer Nutrition Guide, page 55 starts the fueling section.  It was often referenced a decade ago, heck I used it to learn about hydration and fueling for my 1st HIM.  I'm not affiliated with Hammer, just some FYI.