My nutritionist gave me a rule of thumb. If I am eating more than 2 hours before my ride go for the protein + carbs. If I am eating less than 2 hours before my ride, carbs only. Otherwise, your energy will be reduced by the body working on digesting the protein.
Even on a 1 hour ride, I've been told to eat/drink 200 calories. If I am on the bike less than 2 hours, I eat carbs only. If I am on the bike more than 2 hours, I add some protein.
After a ride, within 30-60 minutes eat a combination that is 75% carb and 25% protein.
----------------------------------------------------
"I never made "Who's Who"- but sure as hell I made "What's That??..."