Michigan is known as an auto development hub, including for electric vehicles, but cars aren’t the only modes of transportation being advanced there. Engineering students at the University of Michigan are designing, building, and racing their own electric motorcycles.
SPARK launched in 2013 as a student organization that converted motorcycles that run on internal combustion engines to electric propulsion systems. Now, the group completely designs electric motorcycles from the ground up.
“We’re trying to build the whole thing from scratch — our own custom frame, our own custom battery — basically trying to use as little off-the-shelf parts as possible,” said Riley Hargrave, SPARK manufacturing and battery development director.
SPARK members’ focus has evolved over time from simply proving the electric motorcycle concept to pushing the technology’s limits at races.
“We wanted to promote the sustainability of electric vehicles by building this motorcycle,” Hargrave said. “Slowly, I think the team kind of developed into caring a lot more about racing and speed.”
Testing new technology’s limits
About 40 students currently are on the SPARK team dedicated to building the newest bike, ATLAS. Their goal is to compete in the Isle of Man TT race in 2024.
The team aims to give ATLAS a more powerful motor than previous versions and to reach speeds of 160 mph. As the “heart and soul” of the motorcycle, the battery is getting a lot of attention and is an area ripe for innovation.
“The battery field is rapidly advancing, so we’re looking to tap into some of those newer technologies that will help us get the weight of our bike down and get more power out of our battery pack,” Hargrave said. “When you’re designing a bike, range and power are kind of trade-offs.”
Designing the bike is a balancing act of battery power vs. range. Adding a more powerful battery could increase range, but that could increase the weight and ultimately reduce performance and speed. Therefore, lightweighting is a project focal point.
“We’re taking into account weight everywhere, with the materials as well as the [battery] cells, and making sure they’re lightweight but also power dense,” said Katarina Kovacevic, SPARK brakes and running gear lead.
This bike uses some composite materials such as carbon fiber, which is both light and strong.
“That’s something that’s relatively new to us,” said Will Olenich, SPARK chassis design lead. “I’m trying to use carbon fiber in a more structural sense, rather than just using it for the aerodynamic elements of the bike.”
The team also is starting to use generative design. This concept involves design software that relies on artificial intelligence to put material in places where it’s needed and remove it in other places, resulting in durable structures that best support load. The structures can be manufactured with 3D printing.
In addition to speed, the team prioritizes the bike’s quality and safety to ensure the driver isn’t at risk. ATLAS driver David McPherson is a professional motorcycle racer and provides valuable input that helps the SPARK team with ideas for improvement.
“The best feedback we get on the actual design of our motorcycle probably comes from a rider — the people that know motorcycles for years and have ridden them,” Hargrave said. “A lot of our help also comes from professors, people who know batteries, people who know manufacturing techniques. As far as people who really know electric motorcycles, I’d say there are very few.”
In addition to building vehicles of the future, SPARK members say they’re building both professional relationships and friendships.
“It’s a very unique opportunity compared to the other project teams that we have at the University of Michigan, because it’s very custom-built and we’re at the forefront of this industry of the electric motorcycle,” Kovacevic said. “I, personally, made a lot of friends on the team. … I’m very happy I joined.”
Bumps in the road
Naturally, research and development isn’t always a smooth ride. The team members say they’re learning a lot along the way while overcoming challenges.
“Everything ends up being twice as hard as we anticipated,” said Olenich. “Everything’s super intertwined and complicated, especially as we’re in these early stages of design.”
The intertwined nature of the e-motorcycle components, systems, and operations pushes all the team members toward greater collaboration.
Besides lightweighting and balancing range and power, “there are also a lot of challenges with packaging for an electric motorcycle vs. internal combustion,” Kovacevic said. “We have had to innovate how we can make the battery a structural component on the motorcycle. That’s been a very unique challenge.”
The SPARK team is currently in the design phase for its most current e-motorcycle. They plan to start building it later next year.
After the Isle of Man TT race in spring 2024, the ATLAS sponsors will have a chance to showcase the motorcycle at conferences and industry events. The team also anticipates continuing to race that bike as they build the next model.
Eventually, the e-motorcycle will serve as a teaching tool for new SPARK members, especially considering the lack of resources for teaching electric motorcycle design. They’ll learn about the components by taking it apart and putting it back together, for example.
Meantime, SPARK will continue to add new members.
“It’s kind of hard to know you’re into this until you join,” Hargrave said. “It is an experience you can’t find anywhere else.”
Photos courtesy of SPARK.