There are many reason why it can't just be added to wikipedia. Wikipedia dislikes anything that is and opinion and not fact, some of the articles like the best way to put on grips for example would never fly. Wikipedia is also some what against in depth niche articles. Think of it this way, anything you wouldn't find in a hard copy Encyclopedia doesn't really belong on wikipedia. Sure you could probably put a page up explaining the various types of bicycles and their components, but if you wanted to make a page about assembling and maintaining a freecoaster hub it would get taken down.