What is Bike Excuse?
An overused excuse that hides a person's true intentions.
(Coined from Pokemon, where Misty always followed Ash until he "paid her back for wrecking her bike". She would use this "Bike Excuse" whenever confronted about why she still followed Ash, when in reality it was because she loved him.)
Person A: For the hundredth time, I'm sorry for barging in on you, I was looking for the bathroom.
Person B: Oh, don't give me that Bike Excuse, we all know it was because you wanted to see me change.