Bicycles

Aramid/carbon-framed X-9 Nighthawk looks like the stealth fighter of bicycles

Aramid/carbon-framed X-9 Night...
The X-9 Nighthawk is a prototype bicycle with a frame made from aramid/carbon fiber sandwich panels
The X-9 Nighthawk is a prototype bicycle with a frame made from aramid/carbon fiber sandwich panels
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The X-9 Nighthawk complete bicycle, on display in Berlin
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The X-9 Nighthawk complete bicycle, on display in Berlin
The aramid honeycomb material, used in the X-9's panels
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The aramid honeycomb material, used in the X-9's panels
The X-9 Nighthawk frame weighs in at about 1.4 kilograms (3.09 lbs)
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The X-9 Nighthawk frame weighs in at about 1.4 kilograms (3.09 lbs)
The X-9 Nighthawk also features a custom carbon fiber fork, stem and handlebars
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The X-9 Nighthawk also features a custom carbon fiber fork, stem and handlebars
The X-9 Nighthawk is a prototype bicycle with a frame made from aramid/carbon fiber sandwich panels
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The X-9 Nighthawk is a prototype bicycle with a frame made from aramid/carbon fiber sandwich panels
The X-9 Nighthawk's custom carbon fiber stem and handlebars
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The X-9 Nighthawk's custom carbon fiber stem and handlebars
The X-9 Nighthawk is a prototype bicycle with a frame made from aramid/carbon fiber sandwich panels
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The X-9 Nighthawk is a prototype bicycle with a frame made from aramid/carbon fiber sandwich panels
The X-9 Nighthawk has a commercially-available belt-drive and hydraulic disc brakes
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The X-9 Nighthawk has a commercially-available belt-drive and hydraulic disc brakes

Slovakian mechanical engineer Braňo Mereš has created some pretty nifty one-off bicycle frames over the past several years. Some of his construction materials have included riveted-together strips of titanium, a woven bamboo fiber/epoxy resin composite, and carbon fiber rods. With his latest creation, the X-9 Nighthawk, he has taken yet another approach – the frame is made from sandwich panels that have an aramid core and carbon fiber skins.

Aramid is a tough, heat-resistant synthetic fiber that is used in products such as body armor fabric. The panels used for the X-9 are made of an aramid-based material produced in an open honeycomb pattern, allowing for a balance between structural integrity and low weight. Mereš used a water jet to cut these panels to size, connected them to one another, then laminated sheets of carbon fiber over top.

The completed frame weighs approximately 1.4 kilograms (3.09 lbs), although Braňo told us that weight wasn’t his primary concern with this project. “The goal of the experiment was mainly to design the first bicycle frame ever using honeycomb sandwich panels,” he said. “This material is widely used in the aircraft industry and offers a very good stiffness/weight ratio compared to pure carbon composites. The weight could be much lower if using more suitable and lighter epoxies, which I had unfortunately no access to.”

The X-9 Nighthawk also features a custom carbon fiber fork, stem and handlebars
The X-9 Nighthawk also features a custom carbon fiber fork, stem and handlebars

To build the frame into a complete single-speed bike, Mereš added a carbon fiber fork, stem and handlebars, which he created specifically for the X-9. He also equipped it with a saddle of his own design, along with off-the-rack wheels, disc brakes, and a belt-drive drivetrain. He told us that it rides well, although he plans on test-riding it more in the near future.

The X-9 Nighthawk had its first public display earlier this month at Berlin Fahrradschau 2012 (The Berlin Bicycle Show), where it was reportedly well-received. Should anyone be wondering, incidentally, Braňo assures us that the images of the X-9 accompanying this article are all photographs, not renderings.

Source: Braňo Mereš Engineering and Design via Bicycle Design

8 comments
Gadgeteer
First frame using honeycomb? He's a little late. Nomex honeycomb was used in a frame at least 20 years ago. More recent frames already on the market also use honeycomb. And I wouldn't want to ride on that with all the sharp corners on the tubes and stem. Crashes are almost inevitable on any bike.
Saikoss
Yes, honeycombs are used for the frame tubes for many years. As he wrote, he used the sandwich panels, as far as I know flat panels were not used before. Anyway as an experimental frame it's a very nice work.
YukonJack
Once again we're left to assume that since no price was mentioned that we can not afford to buy one.
Slowburn
I'll take high alloy steel thank you.
Gregg Eshelman
Yet another butt in the air, nose to the ground back breaker of a bike. Where are the innovative bikes that are also comfortable to ride? Comfort! How's that for an innovation?
Robert Duckmanton
Well, who wants to be invisible to radar? Maybe the bike is so good,one is ever in danger of exceeding the speed limit!
Mr Stiffy
It's perfectly FINE to make a bicycle out of anything - as long as it met the general idea of a properly engineered product - flat panels included. What is so blatantly obvious is that I will give the terminal moron "Darwin Award" to the designer for his use of SQUARE edges and sharp corners on a vehicle that has some significant speed, and not infrequently has major impacts with the "delicates" of the body - including skin, sinew, muscle and nerves over bone etc... Irrespective of whether the rider is a BOY or a GIRL - I would be SERIOUSLY worried about banging that bar or head stem into my crotch. That is not like "Ooooooooooooooooooooooooo" and crippled for a while. This bike will strip meat from the bone in a crash. This is a BAD design.
mommus
correct me if I'm wrong, but aren't honeycomb materials more suited to panels and large flat sections rather than narrow tubes like bike frames?