Quantcast

Anothe new internal hub

Discussion in 'Downhill & Freeride' started by davod, Oct 23, 2005.

  1. davod

    davod Chimp

    Rep/Likes:
    0 / 0
    Joined:
    Jun 13, 2004
    Messages:
    32
    I'm surprised that this wasn't beaten to death earlier, it was at interbike.

    picture story
     

    Please register to disable this ad.

  2. Incubus

    Incubus Monkey

    Rep/Likes:
    4 / 0
    Joined:
    Oct 17, 2001
    Messages:
    562
    Location:
    Boston, MA
    Wow. That's an interesting take on it. Almost so simple it's silly.
     
  3. Spitfired

    Spitfired Monkey

    Rep/Likes:
    5 / 0
    Joined:
    Jun 18, 2004
    Messages:
    489
    Location:
    Rochester, NY
    that is VERY cool.
    I'd like to get my hands on one...
     
  4. Thrillkil

    Thrillkil Monkey

    Rep/Likes:
    0 / 0
    Joined:
    May 25, 2005
    Messages:
    595
    Location:
    Isla Vista, CA
    could this be the affordable internally geared hub we've all been waiting for?
     
  5. Sir_Crackien

    Sir_Crackien Turbo Monkey

    Rep/Likes:
    4 / 0
    Joined:
    Feb 7, 2004
    Messages:
    2,052
    Location:
    alex. va. usa.
    don't think that thing will be even remotely inexpenise if it is to work right. the thing is working under a ton of pressure (actually probibly more). i can see this thing slipping under high loads of sprinting.

    cool idea though
     
  6. Thrillkil

    Thrillkil Monkey

    Rep/Likes:
    0 / 0
    Joined:
    May 25, 2005
    Messages:
    595
    Location:
    Isla Vista, CA
    one of the benefits they list on their site is ease of manufacture, so I guess we'll just have to wait and see.
     
  7. Nately27

    Nately27 Monkey

    Rep/Likes:
    0 / 0
    Joined:
    Jul 29, 2003
    Messages:
    121
    very nice...
    they buit a wicked cool lookin prototype: (dl the movie)
    http://www.fallbrooktech.com/02_Demo.asp

    interestingly enough, I saw this very CVT a few weeks ago in a paper on Variable speed wind turbines on NREL.gov. go figure
     
  8. Inclag

    Inclag Turbo Monkey

    Rep/Likes:
    8 / 31
    Joined:
    Sep 9, 2001
    Messages:
    2,322
    Location:
    MA
    Check out the video at Fallbrook Technologies. That is some beautiful machine work!
     
  9. Dirtbike

    Dirtbike Monkey

    Rep/Likes:
    0 / 2
    Joined:
    Mar 21, 2005
    Messages:
    594
    Location:
    eastbay
    Wow! That thing is a crazy simple concept, yet so effective. Id love to try one.
     
  10. zedro

    zedro Turbo Monkey

    Rep/Likes:
    3 / 0
    Joined:
    Sep 14, 2001
    Messages:
    4,160
    Location:
    at the end of the longest line
    its mentioned on their site that one of the applications would be used for wind turbines. I'm kinda with the Sir on this though, i'm a bit skeptical on its ability to provide the "torque density" required (as they put it) for a more aggressive application. It's too bad they dont provide any data, if it works as stated it could be the holy grail.

    Vicious rumor dept: didnt DW mention he was persuing a new tranny technology to be applied in a g-box format?
     
  11. Nately27

    Nately27 Monkey

    Rep/Likes:
    0 / 0
    Joined:
    Jul 29, 2003
    Messages:
    121
    Yeah, I dont think they have the data to extrapolate up to wind turbine sized applications. I say that because in that NREL paper, they simply assume that it could take the torque loading and would only add 20,000 to the cost of the gearboxes already used. In some ways its not a stretch though, becuase they do state they can add more of the planetary balls to increase capacity, up to 12.
     
  12. zedro

    zedro Turbo Monkey

    Rep/Likes:
    3 / 0
    Joined:
    Sep 14, 2001
    Messages:
    4,160
    Location:
    at the end of the longest line
    not only that but use multiple units inline like how planetary systems are arranged in car automatics
     
  13. zahgurim

    zahgurim Underwater monkey

    Rep/Likes:
    6 / 12
    Joined:
    Mar 9, 2005
    Messages:
    1,101
    Location:
    lolAsia
    Wow, if it actually works, this is a cool step forward.
    I'd love to get my hands on one for testing.

    Any pictures of the shifter?
     
  14. Dirtbike

    Dirtbike Monkey

    Rep/Likes:
    0 / 2
    Joined:
    Mar 21, 2005
    Messages:
    594
    Location:
    eastbay
    The shifter would most likely be a grip shifter of sorts.
     
  15. kinghami3

    kinghami3 Future Turbo Monkey

    Rep/Likes:
    6 / 0
    Joined:
    Jun 1, 2004
    Messages:
    2,241
    Location:
    Ballard 4 life.
    Awesome idea! I didn't think it would work until I saw that there was a horizontal axle going through each ball. I can see grip shift working better than any other method, but I hate the way it feels.
     
  16. davod

    davod Chimp

    Rep/Likes:
    0 / 0
    Joined:
    Jun 13, 2004
    Messages:
    32
    I think it's funny that this is called the 'NuVinci', and another cvt hub posted earlier was called the nupace of something.......
     
  17. zedro

    zedro Turbo Monkey

    Rep/Likes:
    3 / 0
    Joined:
    Sep 14, 2001
    Messages:
    4,160
    Location:
    at the end of the longest line
    being an indexless system i could see a bunch of different solutions, even electronic shifting (see how they shifted by rotating that handle? replace with a small DC servo).
     
  18. zahgurim

    zahgurim Underwater monkey

    Rep/Likes:
    6 / 12
    Joined:
    Mar 9, 2005
    Messages:
    1,101
    Location:
    lolAsia
    I could see electronic shifting being pretty cool...two thumb buttons, one to move your ratio up, and one to move down.
    Or, just an old-school non-indexed friction shifter.

    I'd stay away from gripshift style if I was designing it myself, as they are indexed and have a pretty heavy activation pressure to move them, as you don't want to jostle your ratio while riding something bumpy. I'd want to keep a light, non-indexed action on the shifter, so it would be easy to find your ideal ratio.
     
  19. dw

    dw Wiffle Ball ninja

    Rep/Likes:
    5 / 0
    Joined:
    Sep 10, 2001
    Messages:
    2,944
    Location:
    MV
    Toroidal CVTs are nothing new, first patented in 1886, they are widely used in heavy industries. Typically the units are very heavy due to the massive forces involved, and have decent efficicency (80-92%). It will be interesting to see if this technology can successfully be used for bicycles. I am watching. It's a considerable engineering challenge to get the efficiency up to match a chain system. Should be fun to watch!

    Zedro, yes, I am still working and filing for patents, but I am taking it one step at a time. No need to rush it. If what I am working on does in fact work, it will be very good I think. If not, no harm done, it has been fun so far!

    dw
     
  20. Red Bull

    Red Bull Turbo Monkey

    Rep/Likes:
    5 / 0
    Joined:
    Oct 22, 2004
    Messages:
    1,773
    Location:
    970
    ZEDRO! The mindless herds of Newbs on MTBR need you!