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Car designers love big wheels, but engineers hate them

Offering big dubs come with a laundry list of challenges.

Craig Cole Former reviews editor
Craig brought 15 years of automotive journalism experience to the Cars team. A lifelong resident of Michigan, he's as happy with a wrench or welding gun in hand as he is in front of the camera or behind a keyboard. When not hosting videos or cranking out features and reviews, he's probably out in the garage working on one of his project cars. He's fully restored a 1936 Ford V8 sedan and then turned to resurrecting another flathead-powered relic, a '51 Ford Crestliner. Craig has been a proud member of the Automotive Press Association (APA) and the Midwest Automotive Media Association (MAMA).
Craig Cole
2 min read
Genesis GV80
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Genesis GV80

The GV80 wears Genesis' first pair of 22-inch wheels.

Genesis

The Genesis GV80 is the first Hyundai Motor Group product to offer 22-inch wheels from the factory. Designers love putting the biggest rollers they can on vehicles, but this style-first approach can lead to numerous engineering problems.

Speaking at a media roundtable following the GV80's official reveal in Seoul, South Korea last week, Albert Biermann, president and head of the research and development division at the Hyundai Motor Group, explained designers face tons of hurdles implementing wheels of this size. "How much time do you have?" He jokingly said when asked to explain.

"It's quite a job to manage these big wheels because the outside diameter is really huge," Biermann said. "And to control those wheels, especially in Korean driving here with all these speedbumps and potholes and everything, that's quite a job."

Something called unsprung mass is the enemy. This is mass that is not supported by a vehicle's springs. It includes various braking components, suspension parts, hubs and, of course, wheels. The more unsprung mass a vehicle has, the more challenging it is for engineers.

Genesis GV80
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Genesis GV80

The GV80 might not look as good with smaller wheels, but it'll definitely ride better.

Genesis

Since larger wheels are heavier, their movement is harder to control. Biermann said you can soften a vehicle's suspension to compensate and give a smoother ride, but if you go too far, there will not be enough wheel control, which is bad for handling. "So, you have to play this game where you have to find the right balance between very smooth body control but still have enough wheel control," he noted. "And with these big wheels that's quite a challenge."

After a brief stint in the GV80's driver's seat, I can attest the ride quality is smooth, though not quite as creamy as I expected. You sense a lot of mass moving around underneath your feet while traversing bumps or broken pavement.

The vehicle I drove was a Korean-spec model, tailored for a country full of speed bumps, Biermann said. The chassis tuning will be different for other countries -- unique for the US or Australia, for instance. "It will be [a] very nice, balanced car. It will drive differently from what you drive today," he said.

When asked about the GV80's suspension tuning for American roads, Bierman said, "I wouldn't call it stiffer. It has, maybe more body control." He noted it will be on the "refreshing side" compared to the Korean tuning. Also, don't expect fancy magnetic dampers or an air-suspension system in this Genesis SUV. "We are really happy with steel springs," said Biermann, a simpler and likely far less expensive solution.

2021 Genesis GV80 hits the streets of Seoul

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