Bikes are a bit "too" efficient, it doesn't burn a lot of calories when riding at a moderate pace.
A good rule of thumb is around 20-25 calories per mile, often closer to 20. (Long climbs and pushing a fast pace burns more of course.) So a 30 mile ride might only be 600 calories.
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I would come home from a fairly fast group ride and eat a lot of food, I was hungry and tired. It's likely that was a net calorie gain!
A long, steady easy effort ("Zone 2" heart rate) can be good. It's a pace where you can recite the whole alphabet in one breath, where your breathing is easy. A longer ride at this pace can help your body to burn fat reserves instead of carbs, and I'm often not overly hungry afterwards.
A hard ride, with intervals of full effort mixed with easier recovery riding, is good for boosting your cycling muscles. Maybe once a week.