Anyways........................... back to the main thread question..
In my opinion, commuting by bike can be much much cheaper than by car or motorcycle. Why? bc the cost can really be kept at a minimum and there is no gas to pay for..
HOWEVER, most bike commuters are also enthusiasts, and that creates the opposite effect when it comes to savings, bc an enthusiast will upgrade parts of the bike that could be just left alone until they broke. In general when you are an enthusiast of something you will spend more money than you would if you weren't