Bicycles

IsoTruss-tubed Delta 7 bikes look funny, but boast high strength to weight ratio

IsoTruss-tubed Delta 7 bikes look funny, but boast high strength to weight ratio
The Delta 7 Arantix mountain bike, featuring carbon fiber/Kevlar IsoTruss tubes
The Delta 7 Arantix mountain bike, featuring carbon fiber/Kevlar IsoTruss tubes
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IsoTruss tubes coupling with a solid carbon fiber lug on a Delta 7 bike
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IsoTruss tubes coupling with a solid carbon fiber lug on a Delta 7 bike
The Delta 7 Arantix mountain bike, featuring carbon fiber/Kevlar IsoTruss tubes
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The Delta 7 Arantix mountain bike, featuring carbon fiber/Kevlar IsoTruss tubes
The Delta 7 Ascend road bike, featuring carbon fiber/Kevlar IsoTruss tubes
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The Delta 7 Ascend road bike, featuring carbon fiber/Kevlar IsoTruss tubes
Delta 7's carbon fiber/Kevlar IsoTruss tubing
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Delta 7's carbon fiber/Kevlar IsoTruss tubing
The Delta 7 Arantix mountain bike, featuring carbon fiber/Kevlar IsoTruss tubes
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The Delta 7 Arantix mountain bike, featuring carbon fiber/Kevlar IsoTruss tubes
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Go ahead, stare. It’s OK, they want you to. Delta 7 Bikes currently manufactures two of the most unusual-looking bicycles on the market, the Arantix hardtail mountain bike and the Ascend road bike. Their open-lattice spider-web tubes incorporate patented IsoTruss geometric design, wherein carbon fiber and Kevlar are woven into a network of isosceles triangles. The triangles join together to form pyramid-shaped trusses, which provide incredible structural support while using a minimum of material. If you’re a bicycle-maker looking for something with a great strength-to-weight ratio, it’s hard to beat.

IsoTruss technology

IsoTruss was developed at Utah’s Brigham Young University (BYU), for use by NASA. BYU still owns the patent, but granted a license to Advanced Composite Solutions to develop, produce and market products using IsoTruss technology. Advanced Composite Solutions owns Delta 7, hence the funny-looking bikes. IsoTruss is most commonly used to build things like masts, towers, beams and pillars - although it can also be used to make flat objects.

While Delta 7 uses carbon fiber, IsoTruss products can be made using just about any type of weavable fiber (including bamboo) and resin. Because it uses less raw material than conventional methods, IsoTruss can legitimately be called an environmentally-friendly and cost-effective process. Unlike materials such as metal and wood, IsoTruss products won’t rust or rot, they have low wind resistance, and don’t require toxic preservatives. And, despite its complex appearance, IsoTruss is possible to produce using automated techniques.How it applies to bikesInterestingly enough, one of the items that BYU students made to showcase IsoTruss was a mountain bike - the bike that became today’s Delta 7 Arantix. So, what makes IsoTruss particularly well-suited to high-end bike-building?

  • Fantastic strength-to-weight ratio - it can be up to 12 times stronger than steel, while weighing ten times less (depending on the application)
  • Because of the redundant nature of its grid system, damage to one section of the frame remains isolated and can be repaired, as opposed to conventional frames that usually have to be entirely replaced
  • Frame design can be fine-tuned by adding more fibers on the sides for better lateral stiffness, or using less on the top and bottom for more vertical give
  • High-stress areas can be reinforced by using thicker fibers and/or more trusses
  • It reportedly gives a very stiff, responsive ride

Looking at the mountain bike, however, one big question does come to mind... Won’t those tubes get packed full of mud? Apparently, every frame comes with a set of Lizard Skins neoprene covers, to keep that from happening. Is that an ugly and/or awkward solution? Perhaps.

You want one?

Because Delta 7 used to weave all of their frames by hand, the Arantix was likely the world’s most expensive production mountain bike, at $US11,995. Now, thanks to in-house, mechanized production, the price has dropped to a slightly more reasonable $8,495, or $4,895 for the frame only. The Ascend road bike will set you back $10,995, or $5,995 for the frame only. Both frames weigh in the neighborhood of 1050 grams (2.5 pounds)... and that’s without the dirty Lizard Skins.

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8 comments
8 comments
DemonDuck
Yeah great... what about wind resistance. Why not just drag a bucket behind you.
Seriously, do any of these industrial designers use what they design?
Mr Stiffy
Nice - but rather ungay.
Me thinks, OK when a conventional metal frame meets hard object at great speed, the forks and frame buckle between your crushed kneecaps and sometimes you might just bang your balls on the head stem.
V-painful.
So I am wondering with the artistic ambiance of a space frame, is one expected to forgo the ball banging and get impaled on the top beam - as it runs through your guts somewhere between the pubic bone and the navel?
Aerodynamic issues aside, I kind of like the idea of a space frame thing, except the more magnificent the technology the more impossible / costly it is to repair and the more throw away it is....
Kind of like a glass frisbee.
Tho a good quality brazed steel frame has the moderate issue of weight, it is infinitely and easily repairable.
fenriq
I got a chance to test ride an Arantix at last year\'s Sea Otter Classic and really liked it (hard to believe on a bike that costs more than my car, I know). The frame was extremely responsive and stiff and it got more stares than a drag queen juggling flaming Barbie dolls on a unicycle. But, if I had the duckets, I\'d drop them on an Ibis Mojo SL before one of these. Its a neat bike but I\'d be hard pressed to say its $8500 neat.
adam
Demon Duck..i dont think the lattice is an Industrial Designers idea..
I wouldnt be thinking about the air resistance (you body makes *quiet a bit*) but cleaning all the gravel and mud out might be a pain. Dont know why, but i think of a cheese grater against my legs...
Think ill spend a tiny part of the money on losing a couple of pounds on my own body weight instead.
saying all of that...anything new for two wheelers is great!
semperloco
There is something about \"weighs 10 times less\" that I don\'t understand. I might understand if they mean 1/10th as much, but that is not what they said. Ten times what less?
jimbo92107
Q: How do you make a small fortune in the bicycle business? A: You start with a big fortune...
This bike is a great example of that truism. The cost and difficulty manufacturing this thing pretty much guarantees that it will never be more than a curiosity.
heldmyw
Now look what you did, semperloco! You hurt a marketing guy\'s feelings!
If he had a heart, it would be broken...
But chances are, he\'s looking at wannabe bike racers and gloating about gutting them for 8-10K for a pedaltoy.
Of course there is no law that says a fool must be allowed to keep his money.
John in Brisbane
Nice idea but forget the bikes for anything other than proof-of-concept. Put this type of tech into serious production and make lightweight city cars and aircraft structures out of it - have a computer program to automatically create the best structure and then build it for you... A sign of things to come for sure.