As the final project for my machine design course at SFU, I designed a complete single-cylinder, 2-stroke dirt bike engine intended for high-performance applications. This included creating all major components (such as the piston, crankshaft, connecting rod, head, and jug) while ensuring each part met manufacturability standards and exceeded typical industry safety factors.
The main challenges I had to work around during the design process were as follows:
- Each part needed to withstand 1000 psi combustion pressure and dynamic forces at 11,000 RPM while maintaining a safety factor of at least 3.
- All designs had to be optimized for real-world manufacturing methods like casting, forging, and CNC machining.
- Finite element and motion analyses in SolidWorks had to be used to validate strength, fatigue life, and system compatibility across all components.
Through multiple iterations and stress simulations, I improved the geometry, reduced weight, and resolved stress concentration issues in critical areas such as the piston wrist pin and connecting rod ends. The final engine design is robust, manufacturable, and ready for integration into a full dirt bike system.
To validate performance and durability, I ran SolidWorks motion studies at 11,000 RPM to extract peak dynamic loads, then applied these to individual components in static stress analyses. Each part was tested under both combustion and inertial forces to ensure a minimum safety factor of 3. Fatigue simulations were also performed where possible to confirm long-term reliability, leading to several design refinements that improved strength and eliminated stress concentrations.
And finally, I created detailed technical drawings for all components and the full assembly, highlighting key dimensions, tolerances, and mounting interfaces for manufacturing and integration.
