The article describes how it is possible to use 3D printing for printing belt wheels for bicycles. New categories of bikes keep appearing in the market. For the use, specially cities that are bikes, that use belt instead of a traditional chain. With new generations of belts, this power transmission can be used on mountain bikes. But a belt-driven bike must have a special frame, because the belt cannot be disconnected like a classic chain. Even with modern 3D CAD applications a company needs to make a prototype and check their design. That is not only important for the function of the bicycle, but also to prove the assembly or maintenance processes. In comparison with a chain, the belt-driven system is more expensive. For small companies, it is then difficult to buy different gearing combinations, just for checking the design. In this case, the 3D printing comes in handy, because it can produce very quickly cheap belt wheels with different tooth combinations or design of the belt wheel. With more advanced methods (like the selective laser sintering) of 3D printing, it is possible to produce even functional belt wheels that have the same ore even better properties compared to traditional injection molding. This article shows the possibilities in the prototyping of belt wheels with different 3D printing methods.