Let me just say that I am in no way a professional cake decorator. I wish I had the skills and equipment to do so. The equipment that I do have, is a plastic tube with maybe 5 decorator tips that I bought at the tienda de 10 pesos. (Mexican version of the dollar store) I'm a firm believer in making the best out of what you have on hand.
So, here is my version of a bicycle cake, for anyone who might be interested in decorating a cake.