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Gravitybike HQ

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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!

For more: www.gravitybike.com.au
 
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 
Aron3131 year ago
Can you say it in mph?
just divide by 1.6 ;)
or multiply with 5/8 if that suits you better
Ok thanks.
Oldbear1 year ago
Odd question - but do you have to counter steer at a certain speed? (my motorbikes have been anywhere from 25kmph to 35)
mr fat2 years ago
Is there any gravity bike racing in Queensland?
Dedlee2 years ago
I want to find someone to build me a gravity bike. As of now I ride a BMX doing downhill. Any suggestions?
gravitybike (author)  Dedlee2 years ago
Hey Dedlee
shoot me a email at brett(at)gravitybike(dot)com(dot)au and we can have a chat about it! cheers Brett
how much would you ask for one built just like that?
afleming22 years ago
looks comfortable
calcooper52 years ago
This would be cooler if you put up some instructions on how to build this bad boy
there IS one.
http://www.instructables.com/id/Gravity-Bike/
ive seen that one but it is a completely different grav bike. i would love to build THIS one
tyoung62 years ago
whats the song
TheMaker8882 years ago
dont get pulled over for speeding mate haha
nice bike too, you build it?
russvan2 years ago
that is amazing
TwistyTIE2 years ago
oh my that design is just asking for a small bike engine to be put on it :P
Ceiling cat2 years ago
I love that you're wearing Converse high-tops in the video. Probably some of my favorite shoes. I've been wearing mine a lot lately.
gravitybike (author)  Ceiling cat2 years ago
Hey CC, they are the best shoes and have followed me all over the world on the bike! :)
rimar20002 years ago
WOW! That is wonderful! It is a pity that my area be totally plain.

The bike seems very strong. Good design.
muy diferente a la planilandia de La plata, no se puede andar ni en patineta, por el empedrado.
Sí, la pendiente más alta y pronunciada que tengo a 200 kilómetros a la redonda es el acceso a la autopista...
jajaja, es verdad. Aunque descubri que todas las calles son planas hasta que te subis a la bici y te das cuenta que estan todas en subida.
notingkool2 years ago
is awesome, i wish i live in a place with that road. it's ideal to longboard and to back home without efford
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