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 :Mind you, I wrote ""it sounds like"", not ""it is a"". It was a description of the noise, not of the  object itself. – This noise consists of four equal strokes. In my opinion, these equal strokes come neither from a real kick-start nor from a real door. Perhaps we two at least agree that the noise is supposed to symbolize a ""goodbye"" (in an agressive way). – Anyway, this is all original research and therefore deleted on Wikipedia. Thank you for sharing your thoughts. Cheers    

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