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A Seat for the Mountain Biking Set

Joshua Mackenroth seeks investors for Gravity±Sea

According to local inventor and attorney Joshua D. Mackenroth, there’s no doubt his Gravity±Seat invention will be a huge success in the bicycle racing industry.
Mackenroth spent the past three years working on an idea that has been rolling around in his head since 1988.  “I’ve always wanted to invent something” says Mackenroth. “But I never really had the time to do it.”  That all changed for him in 2007 after he lost his job when the company he worked for was purchased by a hedge fund.  “I searched for many months to find another job. There was nothing out there. I realized that I had to create my own opportunity, and that nobody was going to give one to me in this economy. That’s when I thought about developing an idea for bicycle racing that I came up with 20 years ago in college.”
The concept was derived from Joshua’s passion for motocross racing.  He started racing motocross when he was 15, and raced competitively off and on for the next 25 years.
“I noticed a huge problem with the way bicycles cornered that the motorcycle guys didn’t have, and that’s the ability to corner effectively by dropping your center of gravity down low,” says Mackenroth. “Traditional bicycle seat posts remain in a fixed position. Most of the rider’s weight is placed on the front wheel due to the normal positioning of the rider in relation to the bicycle. This creates a problem when cornering because the unequal weight distribution leads to front end wash-out in tight corners. I thought if the riders were able to lower their center of gravity by moving their body both downwards and back at the same time, they could adopt a more aggressive riding style and turn harder, sharper, and faster.
“You’d see the road bike riders hanging off their bike and dragging knees around the corners, just like the motorcycle guys. It would fundamentally change the way people ride bicycles. Just think how revolutionary that would be.”
Joshua poured himself into making a bicycle suspension seat post that would accomplish all of the above. “When I wasn’t looking for a job, I was working on the bike seat,” he says. It ignited passion inside me that I haven’t felt for anything in a long time. It gave me hope, and reminded me that I still had the choice to pursue my dreams and not accept the way things were.”
He came up with a seat that travels downward at a 45-degree angle, thereby moving the rider’s weight both down and backwards on command with the flick of a lever. He decided to call it the Gravity±Seat.  His invention became the first suspension seat post in the world designed especially for road bikes.
“I learned a lot during the process. I taught myself how to use computer graphics programs and created all of the graphics,” Mackenroth says. “I created my own Website. I learned how to trademark the name Gravity±Seat. It took me three times before the U.S. Patent and Trademark Office would accept my patent application, but they finally did.
Gravity±Seat was officially unveiled in 2009 at the world’s largest bicycle convention, Interbike in Las Vegas.  “It turned a lot of heads,” he recalls.  “My favorite thing to do was lean my show bike up against a post in the convention center and walk a few yards away. People would start swarming the thing, taking pictures and wondering what it was.”
Although the concept was originally intended to work on road bikes, the greatest potential for his invention probably lies in the mountain bike market. While the Gravity±Seat does serve to lower the rider’s body weight, it also acts as an excellent suspension system for the off-road bicyclists, according to Mackenroth. “I didn’t realize it at first, but the downhill and mountain bike market is probably where the opportunities are. There are over 35 suspension seat posts in the market for off-road bikes today, but mine is still the only one with the reverse angle that allows the rider’s body weight to be moved both down and back.  The downhill guys went nuts when they saw it at the convention. And the design has only a couple moving parts, not like some of the contraptions I’ve seen in the marketplace.”
Mackenroth is looking for investors to help bring the Gravity±Seat into production, or perhaps license the manufacturing rights to a large bicycle company.  “I’ve done as much as one person can do to turn this idea into a reality,” he says. “I’m looking for someone who can take it to the next level.”
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