The company designed and tested their first two prototypes in 2012, and many significant design changes were needed. All 22 castings in the engine needed to change, as well as the chassis, electrical, exhaust, and other systems. Electronic fuel injection, new porting, splayed exhaust valves and other refinements were also needed for improved long-term durability, cooling, and oiling.
Redesigning and tooling new engine castings would take about a year, and all of the other changes depended on the new engine design. Instead of waiting a year before moving forward with designing all the new elements, Motus moved forward using a 3D printed engine model.
“If we had waited for the metal engine prototype to begin the detailed design of the rest of the bike, it would have taken us two years to go from our first prototype to production,” Case said. “With 3D printing, we were able to redesign, tool and build the engine, chassis, exhaust and electrical systems, and other components simultaneously in only one year.”
Motus was already using a uPrint® 3D Printer from Stratasys to print small brackets and bearings for the new bike. But 3D printing larger prototype parts for the engine required a larger system, so Motus Design Director Brian Case used a Fortus® 3D Production System to print accurate models of the castings for the engine exterior.
Each casting was 3D printed as a separate piece and bolted together to test the engine assembly. The assembled engine was then used to design other key components of the bike, including the exhaust system, which was built from steel tubing and tack welded on the 3D model engine.
“Creating a new motorcycle from scratch is a massive, multifaceted undertaking,” Case said. “3D printing played a crucial role by giving us the ability to formulate new ideas and test them the next day.”
Motus’ groundbreaking motorcycle design includes a 6-speed transmission and a custom-designed V4 engine, the first V4 ever used in an American motorcycle. Known as the Baby Block V4, its design is based on the same small block engine architecture found in the most cars and trucks.
“When we received the metal prototype engine, we removed the plastic model and bolted on the metal engine. Everything fit perfectly and we were able to move immediately into production, Case said. “Revenues only started flowing after we started production, so the year we saved was critical to the success of our company.
The final creations, the Motus MST and MST-R, are the only sport- touring motorcycles in the United States offering riders performance and speed that’s comfortable on long open roads. Recently, an unmodified production Motus MST-R motorcycle shattered two world land speed records at the Bonneville Salt Flats.
Built in small quantities with great attention to detail, this one-of-a-kind motorcycle is a dream come true for Motus founders Case and Conn, a dream realized faster than anticipated thanks to 3D printing.
