Design of a multi-purpose motorcycle platform

Abstract

The East African motorcycle transport industry is one of the fastest growing motorcycle markets in the world. This has been due to a tremendous increase in wealth and standard of living over the last decades and the developments these factors trigger, such as road/infrastructure improvement and increase in quantity and quality of product-services. Motorcycles provide a quick, easy and financially accessible way for consumers to contribute to and profit from these developments. The vast distances in East Africa and the lack of a well-developed infrastructure require a smart, social and affordable motorcycle that KONEKSIE is currently developing for the taxi industry. At KONEKSIE, current design work (on both the product and the production system) has been focused primarily on their first motorcycle model, the ‘KIBO K150’. To be able to innovate in the future, it is necessary to broaden research and development activities to explore the opportunities for product portfolio expansion. As a start-up, however, KONEKSIE is faced with limited resources and is in need of an efficient and effective technical solution that enables future expansion. This project has taken on this design problem and has focused on the design of a technical motorcycle platform, which aims at reintegrating KONEKSIE’s existing technical design solutions and combining them with new design solutions to create a multi-purpose chassis platform. At its core, this technical innovation will be focused on connecting the design and the production of different motorcycle designs through a series of new and existing, interchangeable and reconfigurable design solutions. At the foundation of the platform design is a product roadmap, based on trends and developments from KONEKSIE’s market of operations: Kenya, East Africa’s leading economy. While focused on the Kenyan market, these identified market segments might also be relevant outside of East Africa, since the market developments that are at the bases of these segments, are occurring in numerous other countries and regions. The roadmap strategy is built on three high-potential (Kenyan) market segments: private and professional mobility (Type I), cargo focused mobility (Type II) and accessible mobility (TYPE III). KONEKSIE’s ‘K150’ has many commonalities with Type II and as such, an updated ‘K150’ perfectly caters to the cargo focused mobility segment. In the roadmap strategy, introduction of the Type II model serves as a transition phase towards introduction of the platform design. The platform design offers a multi-purpose solution that caters to private & professional mobility and accessible mobility. In the form of two motorcycle models, Type I and Type III, the platform is able to position two strongly differentiated models in the market, while minimising the amount of unique component designs necessary. The multi-purpose ‘design core’ of the platform centres on the design of a new chassis that allows for multiple configurations to achieve different motorcycle types. Through the design of a single mainframe that is compatible with multiple subframes and engine types, the chassis platform is able to reach very different user groups. By offering different engine types and an active but professional riding experience, Type I caters to the needs of the growing entrepreneur and middle class citizen. Type III caters to the needs of the novice (female) rider, for whom ease of use is key. Usability and accessibility can be found in both its technical features (such as a semi-automatic gearbox) as well as in its relaxed and highly stable riding experience. In the platform design, the multi-purpose integration of two sets of technical and usability features does not lead to concessions, but to unification and harmonisation in design and production. The platform based design approach allows for model-bridging solutions, that bring down the amount of components. Through the design of custom chassis connectors, the platform design enables simple engine placement, provides footboard/footstep mounting points and introduces a separable connection for production and assembly optimisation. Together with the unique model-bridging design of the engine mounts, the platform’s crucial engine compatibility is established and concurrently minimisation of the total number of (unique) parts is further achieved. The reduced number of production moulds and tooling necessary, contributes greatly to reducing the need for new investments. However, an important part of the platform design’s investment reduction is achieved by reintegration of existing investments. Through analysis of time and capital investment related to the development of the ‘K150’ a number of investment intensive components were identified. The platform design has successfully reintegrated the main gusset plates, which required the most sizeable capital investment in the ‘K150’ design. Together with the near-complete adoption of the ‘K150’ swingarm assembly in the platform design and the standardisation of KONEKSIE bending tools, more than 60 percent of the original ‘K150’ chassis investment has been reinvested in the new Type I and Type III. Creation of a digital and physical prototype of the platform design has allowed for validation of the technical design, the usability and platform strategy. Technically, the design has been validated on its assembly, structural integrity and manufacturability. In CAD, an additional FEM analysis was conducted in order to improve the strength of a common weak point, the steering head tube area. In terms of usability, two user sessions have been held to assess ergonomics. Specifically, the Type III configuration was tested to improve mounting of the motorcycle by novice users, through the use of a lowering in the frame, the step-through. Finally, a comparison was made between a traditional non-platform based design approach and the proposed platform design approach to validate the platform strategy. Comparison results showed that implementation of a multi-purpose platform design strategy would require 41 percent less parts to be designed. As each design requires time and capital investment for its realisation and production, this would mean that the platform-based approach would save KONEKSIE a considerable amount on investment while still being able to provide the necessary differentiation and expansion within the market. The final platform design, focused on the rolling chassis, provides a great foundation for further development of a complete motorcycle platform. The design of the rolling chassis is an important, first part of a whole.