What do you mean by a 'good ride'? If that is all you are going to consume, then no. Milk contains the slower protein casin and has a lower glycemic index. After a hard ride you are looking quickly replace what you spent with a mix of high and maybe medium glycemic index carbs and some medium to fast protein like whey - the amounts and ratios would of course depend on the workout. Milk can be a part of your recovery meal, but it shouldn't be the only thing.