Your body can only process about 1 gram of carbs per minute at most, so I generally target around 45-60 g of carbs per hour. This is about 270-360 calories per hour. I also fuel up with a waffle or pancakes and a couple eggs two hours before I start a long ride and start eating on the bike starting around hour
#2 .
For example, on a six hour ride I would start off carrying around 300g of bars, cookies, and dried fruit. It’s best to kind of continually eat during the ride so that you’re constantly adding fuel to the fire. Once you fall behind and feel hungry it’s hard to catch up.