That amount of exercise will not result in weight loss but you will improve your cardio and have stronger butt, torso, and legs muscles. Only cutting calories, especially carbs, will result in significant weight loss. The keto diet is going to provide the best results and it is a healthy long term diet.

It also takes a certain amount of time for the body to consume all the glucose and start to burn fat. A 4 hour ride will do far more in this area than 4 one-hour rides of the same total distance.