To agree with one of the developers’ dodgy claims, Shark Wheels really are a revolution in wheel technology. By “revolution,” I mean their products tend to revolve around a central axis. Outside of this simple prerequisite for the word “wheel,” I can’t see much advantage these wobbly-looking things would provide over the 5,500 year old tried and true “circle” models.
The skateboarding world is rife with market-minded inventors promoting gimmicky products to children. Every now and then, however, some of these products find their way into mainstream acceptance. Thanks in part to a highly successful kick-starter campaign, one LA-based start-up has already begun production on their Shark Wheels, advertised as the SQUARE skateboard wheel that shreds! As a lifelong skateboarder with a physics degree, I found the initial claim suspect. I seem to remember most wheels I’ve encountered as having a much rounder shape, but one look at the kick-starter page will suggest that these Shark Wheels are squares, circles, cubes and sine waves ALL AT THE SAME TIME.
It’s a perfect cube-
No, it’s not. Very obviously not. Not by a long shot. And contrary to what they say, they don’t look like squares from the side. Nine-of-ten pictures show them from a three-quarter angle that gives the illusion of flat sides. Viewing them along the axle, you can easily tell it would contact the road smoothly in a circle. That’s the entire reason it rolls.
Shark Wheels are faster
I don’t see any side-to-side races between the shark wheel and a traditional wheel. The speed of the wheels on the board relies almost solely on the quality of the bearing within that wheel, sold separately. The reduced contact area argument applies, but any traditional wheel with straight grooves (picture stacked donuts) would have the same advantage. There’s no need for the sine wave here.
Alternating center of gravity allows for superior high-speed stability, eliminating speed wobble
This is stated on the company’s website, sharkwheel.com, and is just plain wrong. Speed wobbles, with which most skateboarders are frighteningly familiar, occur at high speeds when your center of gravity begins to oscillate away from the lengthwise axis of the board. If you don’t stay low and push your weight forward, the wobbles can worsen until you find your face not-so-gently caressing the pavement. This has nothing to do with the centers of gravity of the wheels themselves, which are fixed in the center and don’t alternate.
Furthermore, any extra stability these wheels may provide is probably due to their increased width to accommodate all the extra winding urethane. The same extra wavy width that must slightly hinder aerodynamic properties.
Grip is a mostly a function of how soft the wheel is, usually rated on the durometer scale for skateboarding. Lower durometer wheels are softer and grippier compared to the harder, higher durometer wheels used in street skating. By comparison, Formula 1 cars have wide, soft, smooth wheels because they are proven to grip dry roads best.
Perfect rain/gravel wheels
Perhaps a bit of truth can be extracted here due to the grooves pushing water and sand into the negative space. Though, for rougher surfaces, I’d like to know which direction the grooves are facing at all times so they don’t randomly fit into the wrong crack (or coping) and stop me cold. If you’re off-roading, there are plenty of inflatable treaded tire wheels available that would do a fine job rolling over wet gravel.
All criticism aside, the custom color combinations and variable durometers are intriguing. I’ll give ’em that.
But wait, there’s more! From the kickstarter:
We plan on going into every market with a wheel. It is just a matter of time and money. From military vehicles to bicycles to wheelchairs, we want the Shark Wheel to be identified as the only non-circular wheel in existence.