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Entertainment Hardware

Bicycle Tech Drivetrain Advances Showcased 412

whoda writes "For many years, bicycles have had very few advancements in drivetrain technology. This is finally changing. The newly formed g-Boxx Standard has been incorporated into the new Nicolai Nucleon TFR bicycle frame. This bike uses an internally geared 14 speed planetary gear system, mounted in the center of the bicycle, to drive the rear wheel using a conventional chain. The design allows the chain to run inside of the frame. This removes many fragile components from the bicycle, and allows a more rigid frame structure to be made. Evil Bikes have also shown a protoype Evil 2013i hardtail which also incorporates this new standard - I've found the toy I want for the holidays."
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Bicycle Tech Drivetrain Advances Showcased

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  • by Anonymous Coward on Saturday November 15, 2003 @09:22PM (#7483885)
    It is meant as a downhill bike... 35-40 pounds is average for them... The bikes need to be tough, weight isn't important.

    I wonder what the chain-slap would sound like with the chain enclosed in the swing-arm?
  • by earthforce_1 ( 454968 ) <earthforce_1 AT yahoo DOT com> on Saturday November 15, 2003 @09:24PM (#7483896) Journal
    Driven through a continuously variable transmission, like those used in many motorcycles. They are more reliable, less prone to breakage than a chain.

    I remember seeing bikes with elliptical gears in an old popular mechanics they claimed match the power transfer curve of the human body, that would lower the gear ratio at the point you have less energy to push. They said it was about 20% more efficient or something like that, but I never saw it catch on much. Maybe the patent fees were too high.
  • by avi33 ( 116048 ) on Saturday November 15, 2003 @09:32PM (#7483926) Homepage
    You could simply ride fifteen pounds of funk [usrnull.com].

    One gear -> stronger legs, more distributed workout, less to maintain, fewer parts to fail, just mo' fun

    Every once in a while someone spends a crapload of money trying to change the fundamentals of the bicycle, but really, other than the derailleur, not much has changed in over 100 years.
  • by taj ( 32429 ) on Saturday November 15, 2003 @09:43PM (#7483972) Homepage
    "- Bicyclists don't need Continuously Variable Transmissions : human legs are incredibly efficient over a range of speeds from 0 to 13/140 RPM"

    As a retro biker that does it smart going on 40 I suggest you rethink this.

    Hold on their young one. Any 17 year old can do 0-140 rpm but as the joints get older, you need to keep the rpms higher and the impact lower. 90rpm would be about right for all times.

    You can crank for 30 years at 5 rpm but I'd rather let the gears do the work and sleep at night without arthritic knee pains.
  • by Rosco P. Coltrane ( 209368 ) on Saturday November 15, 2003 @09:45PM (#7483981)
    When you lose your rear derailleur in a DH race, your chances of making the podium are slim. Believe me, it happens a LOT, and it gets expensive and very annoying.

    All the good downhillers I know in my neck of the wood have short-tail road derailleurs that don't hang down as much, a big bash-plate around the derailleur and chainstay, and anti-derailling/chainslap/chainsuck rollers on top and bottom of the chainwheel. None of them seem to lose derailleurs a lot ...
  • 9 speeds? (Score:3, Interesting)

    by The Ape With No Name ( 213531 ) on Saturday November 15, 2003 @10:56PM (#7484217) Homepage
    From the G-boxx site:


    The aft system contains a rear hub which houses the cassette assembly, providing up to 9 different gearing ratios


    My Airborne [airborne.net] Zeppelin is all Campy and a 10-speed on the rear sprocket. Combined with a triple up front this is 30 effective gears (and ratios). Shimano is not the only thing on the planet and certainly not the best.


    IANAMTBR (I am not a mountain biker) but those I-drive bottom bracket systems are pieces of shite. Sure they are very adjustible, yada, yada, but when you are 30 miles from fuck-all and it gives up the ghost you'll wish you had a tough-as-nails XTR bottom bracket. Simple is beautiful on a bicycle. That's why I like them. I hope it is light! If it isn't then you are not going to sell this stuff, ever.


    Personally, I am waiting for the Campy/Shimano electric shifts to get cheap enough.

  • by twitter ( 104583 ) on Saturday November 15, 2003 @11:07PM (#7484253) Homepage Journal
    They wear out and provide a terrifying ride. Check Dr. Sharp's 100 year old compendium and see for yourself. It also helps to check motorcycle history because motocycle development took right off of bike tech at the turn of the century. You will find that complicated sprung frames generally have problems. There's a reason most bikes are made in diamond frame sytle.

    That said, the current generation of sprung frame mountian bikes do provice considerable advantages over rigid frames. You will pay for those advantages. If you've got the cash to play, bully for you and have a great time.

  • by trick-knee ( 645386 ) on Saturday November 15, 2003 @11:49PM (#7484564) Homepage
    sorry if I sound like a troll, but I've been a serious cyclist for over 20 years now, done competition at the USA national level (okay, I got waxed, but I was there!), worked in the industry (local shop, major retailer, manufacturer), and have read way too much hype about new stuff. reading the comments here reminds me of a bunch of bike guys sitting around talking about how cool Windows ME was when it came out.

    okay, okay, we're just off our usual topic set here. but someone tell me why this story is on /. anyway. there are several posters here that seem to be actual riders, but the great majority don't seem to be very discerning cyclists.

    first, this supposedly new and supposedly cool design is, as others have already pointed out, just recycled concepts, the main function of which is to separate the consumer from his/her cash.

    these concepts have all been relatively stillborn over the years mainly because they are more expensive, less reliable and heavier than existing designs. plus, internally geared hubs are fine for the grandpa and grandma riding around the retirement community, but they are notoriously inefficient for someone trying to actually go fast.

    reasonable cost is important because stuff breaks. always. even the unbreakable stuff.

    reliability is important because we'd all like to ride home, not walk. plus it keeps us from having to pay for more stuff. this looks like stuff designed for freestyle use, and that stuff gets thrashed.

    light weight is important if you ever have to (a) accelerate the bike (including changing its direction, or (b) go uphill. maybe also (c) put the damn thing on top of your car.

    anyway, these bikes look like expensive pigs using minimally tested technology. we should all be sneering at this.

    I mean, shit, if you don't want your shoelaces to get caught in the chainrings, double tie them. put a fucking rubber band around your pants cuff.

  • by DarkSarin ( 651985 ) on Saturday November 15, 2003 @11:52PM (#7484585) Homepage Journal
    I have a question, tho many probably know the answer. As a disclaimer, I AM NOT A CYCLIST!! (ianac?).

    that said, wouldn't be possible to mount the derailleur ABOVE the gears so that it is not so prone to snag on rocks, etc? I would think that would help a lot.

    Let me know.
  • This year, you may (or may not have noticed) that every rider in the Tour de France was wearing a helmet. They're only allowed to take off their helmets for the last 5km or so of a race when the finish is uphill. Why?

    Well, earlier in the year, a nice young rider with a 2 month old son went over his handlebars in a low speed crash. He bumped his head on the ground, and never woke up. From all accounts, Andrei Kivilev was a nice guy just trying to make it as a pro.

    He was apparently the last straw. Finally, the UCI has instituted mandatory helmet laws for all riders. It's not because it's flashy, it's because they CAN save lives. It's not a guarantee, but neither is a seatbelt.

    The bike that you're asking for is constantly being aimed for, not by bike companies, but by people that try to develop cheap bikes for third world countries, where they're actually a fantastically important asset. Hopefully, they'll also make bikes domestically. I think that something like what you're suggesting could bring cycling back to our overly sedentary society. What we need are cheap, effective helmets and cheap effective bikes. In that, you're totally right.
  • by bfields ( 66644 ) on Sunday November 16, 2003 @12:06AM (#7484698) Homepage
    A state-wide study conducted in the first four years after the introduction of the law showed a 42% reduction in hospital admissions for cycling sustained head injuries. http://www.general.monash.edu.au/muarc/rptsum/es76 .htm

    Unfortunately, others claim that this is mainly attributable to a decrease in cycling: http://www.cyclehelmets.org/papers/c2001.pdf

    It is illegal to ride a bike without a helmet.

    That depends on where you live, of course. Where I live it isn't illegal, at least not for adults.

    --Bruce Fields

  • by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Sunday November 16, 2003 @12:43AM (#7484961) Homepage Journal
    Ever heard of carbon fiber tube? It's inexpensive, and if you need to make it stronger than the preformed tubes provide, you can wrap it in a "sock" of tubular-woven carbon fiber, stretch it tight, and put resin over it.

    Calfee is now working on carbon fiber recumbents, which are being designed by fast freddy, who formerly had the bicycle land speed record on an Easy Racers gold rush with a fiberglass shell.

    Maybe you can repair your chain on the road (if you have some links, and a chain tool) but chains suck. There's a lot of unnecessary friction there and it increases the number of parts on the bike dramatically, especially when you consider that each link is a part.

  • by Equuleus42 ( 723 ) on Sunday November 16, 2003 @02:03AM (#7485419) Homepage
    There is an old adage in the motorcycle industry that goes, "if you have a cheap head, wear a cheap helmet." I think that speaks volumes about people who don't want to wear helmets...
  • by the grand asdfer ( 228243 ) on Sunday November 16, 2003 @02:45AM (#7485671) Homepage Journal
    A german company Rohloff, has been making an internally geared 14 speed transmission for bikes for few years now. The gearing range on it is equivalent to a standard Shimano 27 speed triple chainring system. The only problems with these things is maintenance issues and the cost. I beleive if you had any problems with the Rohloff system, it had to go back to Germany for repair, apparently these things are pretty complicated. The other drawback is price, I believ the Rohloff rear hub/transmission was alot heavier than a standard setup. On downhill/freeride bikes, it may not be an issue, but for cross county/trail bikes it is a real big issue. BTW, mountain bikes can be a very expensive hobby. My downhill bike alone costs ~$3500 US and my Cross Country bike close to that.
  • by Simon Brooke ( 45012 ) * <stillyet@googlemail.com> on Sunday November 16, 2003 @07:13AM (#7486420) Homepage Journal
    I think a whole lot of point missing is going on.

    I've been interested in this project for some time and have been exchanging email with Karl Nicolai about it. Yes, OK, a gearbox is not going to be a win on a road racing bike for a number of reasons, but not all bikes are road-racing bikes. On any mountain bike (I'm particularly interested in cross country bikes, where weight does matter) this is a potential win.

    It's true that in perfect conditions a deraileur system is more efficient than a gearbox. But mountain bikes operate in less than perfect conditions. Sticks and branches get tangled in delicate deraileur mechs and wreck them. The increasingly delicate deraileur chain operates in a cloud of grit particles which cause rapid wear to all parts of the drive train. And the chain operates for much of the time at transverse angles which sap its efficiency - these angles get more extreme as the number of gears increases. So in mountain bike conditions deraileurs don't deliver anything like the efficiency that chain systems offer in optimal conditions.

    The Rohloff [rohloff.de] hub isn't new. It has been an upmarket preferred fit on European touring bikes and recumbents (and some audaxes) for some time. It's a robust, reliable and efficient unit. Furthermore, it's only about 200gm overall heavier than an equivalent deraileur setup. Karl Nicolai's innovation has been to put the Rohloff at the suspension pivot, thus putting all that expensive engineering into the most protected part of the frame and also substantially reducing the unsprung weight.

    However, if the gearbox is going to be around the bottom bracket it doesn't have to be epicyclic, and consequently a cheaper, simpler and possibly lighter gearbox than the Rohloff could be used. Also, you could do away with the primary drive chain, which is an inefficiency on the current Nucleon design.

    The benefits you get are a very much more robust and reliable drive train with even gear spacings. The weight penalty will probably end up less than 100 grammes (perhaps even less as the structure of the gearbox becomes an integral part of the frame), and the efficiency penalty in real world conditions - for mountain bikes - is likely to be nil.

    So I think within five years we'll see gearbox driven cross country mountain bikes wich are competitive in terms of weight and efficiency with deraileur models. The gearbox will not be an aftermarket fit - it will be integral with the frame. It will offer about twelve to fourteen ratios, but as these will all be usable and will be evenly spaced with no duplication this will be adequate to compete with the so-called 27 speed deraileur systems (which typically have lots of overlap and duplication).

I've noticed several design suggestions in your code.

Working...