This report is based on one of my own ideas and describes the development of a propulsion system for a conceptual motorcycle. The main idea is to mount the drivetrain within a hubless wheel and thus fully integrate these two together.The project began with a comprehensive collection of information. This collection mainly focused on an investigation of the traditional automotive drivetrain, tracing different transmission input elements and an investigation of their relative functions.Two visits to the Air Force Museum in Linköping were performed, where the primarily aim was to study different radial engine's physical dimensions.The work with the hubless wheel and the work with the drivetrain were separated in order to facilitate the development of the whole work. Therefore two main problem determinations and one divided specification of conditions were established as the basis for the construction sub-functions.After the reduction of different design solutions concerning the sub-functions, which mainly were carried out through logical reasoning and discussions, two rather similar proposals of solutions remained as a base for further development of the project.The final drivetrain was based on an Australian radial engine from Rotec Engineering, Rotec R3600, which was combined with a hybrid module from the German manufacturer ZF Sachs. This combination reduces the need for a torque converter in the driveline. During start-up the driveline will instead use the the electrical motors high torque at low speeds, which reaches about 770 Nm in this case, and then switch to the combustion engine at higher speeds. The included hybrid technology reduces fuel consumption by almost 15% and also provides the ability to convert braking energy into electrical energy to recharge the batteries. The hybrid technology also offers the ability to connect the electric motor to the drivetrain as an extra "boost" when there is a need for faster acceleration at higher speeds.The work with the hubless wheel resulted in the development of nine separate shafts mounted on the outside of the fixed inner rim. Four radial and two axial bearings were mounted to each shaft. This makes it possible for the outer rim, the tire and the disc brake to rotate freely outside the inner rim. The bearings were selected and dimensioned through a self-developed model concerning possible loads and stresses.Finally the drivetrain was concentric and vibration damped mounted inside the hubless wheels inner rim via a self-developed engine suspension. The impulsion is transferred from the drivetrain to the outer-rim by the spoke system. This system was also designed to reduce vibrations from spreading from the engine to the rest of the construction.The final construction was integrated and visualized as a conceptual motorcycle by Erik Evers, a former student at Luleå University of Technology.The following further development of the project is proposed: Complete the rear wheel mounting to the motorcycle. Determine the final axial center of gravity of the driveline when mounted in the rear wheel. Further develop the engine mount to encompass eight attachment points distributed over two different planes in the inner rim. Develop of one or more drive shafts interconnecting the driveline components. Examine the possibility of transition to fuel injection and digital ignition for better engine operation. Complete the seal between the two rims in the hubless wheel for increased resistance to dirt and moisture.