Gravitybike HQ





Introduction: Gravitybike HQ

Brett Phillips - Gravitybike HQ

A Gravity Bike is a specialised two wheeled bicycle propelled by nothing other than gravity. Without pedals or a chain, Gravity Bike riders rely on steep gradients and gravity to reach incredibly fast speeds. Historically, Gravity Bikes evolved from modifying a traditional BMX where a rider would add weight, alter seating and handlebar positions and change a bikes aerodynamic characteristics in the pursuit of greater speeds. More recently, Gravity Bikes have evolved to become highly specialised and purpose built machines capable of reaching speeds over 130kph from a standing push start.

Gravity Bikes are ultimately built for speed. The steeper and more technical a road or dedicated racing circuit, the greater the adrenaline rush for riders. Fitted with full protective gear including leathers, helmets, gloves and boots, Gravity Bike riding combines the thrill of speed with a love of bicycles.

In 2009, I designed and built this purpose built and highly specialised Gravity Bike. The first of its kind, the bike is a quantum leap in Gravity Bike design and fabrication. The bike is a combination of hand fabricated and CNC (computed numerically controlled) components. The bike was designed from scratch and had to accommodate existing components such as 20'" wheels and mountain bike brakes. The bike has reached speeds of 136kph from a standing push start and assisted me to win the 2009 World Gravity Bike Championships. The only Australian to do so to date. I hope you guys like the build!

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so who made the very first gravity bike??

so who made the very first gravity bike??

i see your in australia, do you know lithgow?
if you do, there is a huge steep windy highway there, which would be great for this, but, there is a cliff on the edge, not too high but still a cliff

"The first of its kind, the bike is a quantum leap in Gravity Bike design and fabrication."

You're probably going to want to change that. A quantum leap is the smallest measurable change.

Atomic Electron Transision 

Can you say it in mph?

just divide by 1.6 ;)
or multiply with 5/8 if that suits you better

Odd question - but do you have to counter steer at a certain speed? (my motorbikes have been anywhere from 25kmph to 35)

Is there any gravity bike racing in Queensland?