Advertise on Bikeforums.net



User Tag List

Results 1 to 8 of 8
  1. #1
    Mr. cost-benefit analysis
    Join Date
    Dec 2005
    Location
    Agua Dulce, CA
    My Bikes
    Surly Crosscheck Single Speed, Novara 9 speed commuter/runabout
    Posts
    437
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Sram Imotion 3 speed hub

    Anyone built a wheel, or at least ridden a wheel with one of these?

    I'm wondering if they've improved on the breed? Or just repackaged it?

    DanO

  2. #2
    Senior Member
    Join Date
    Jul 2003
    Location
    Brooklyn, NY
    Posts
    1,453
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The main improvement of the iMotion-3 over the T3 is the quick-release cable shared with the i-Motion 9. Also, there is now a kids-specific shifter available.

  3. #3
    Senior Member
    Join Date
    Nov 2004
    Location
    Netherlands
    My Bikes
    Wabi Lightning, fixed 13.6 pounds. Cera steel road bike Campy veloce 9s
    Posts
    475
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Internals are slightly different, no longer interchangeable with the old T3

  4. #4
    tcs
    tcs is offline
    Palmer tcs's Avatar
    Join Date
    Mar 2007
    Location
    Parts unknown
    Posts
    4,144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Exploded diagrams indicate this is completely different from the T3. It has an in-board shift cable (does not go out the end of the axle) and shifts "backwards" (a broken cable would put the hub in LOW gear like the old Sturmey "X" hub, not high gear like the S-A AW, Shimano and SRAM's own T3). OLDs are 130 for freewheel and coaster, 135 for the disc brake version, and from the diagrams (I've not seen a real one, sorry) it appears there is not much scope for narrowing the OLD on these. The iM3 design doesn't not require any special tools for dis/re-assembly. The iMotion3 coaster version uses the historic Sachs Torpedo roller actuation brake.

    tcs
    "When man first set woman on two wheels with a pair of pedals, did he know, I wonder, that he had rent the veil of the harem in twain? A woman on a bicycle has all the world before her where to choose; she can go where she will, no man hindering." The Typewriter Girl, 1899.

    "Every so often a bird gets up and flies some place it's drawn to. I don't suppose it could tell you why, but it does it anyway." Ian Hibell, 1934-2008

  5. #5
    Senior member Dan Burkhart's Avatar
    Join Date
    Oct 2004
    Location
    Oakville Ontario
    Posts
    4,862
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tcs View Post
    Exploded diagrams indicate this is completely different from the T3. It has an in-board shift cable (does not go out the end of the axle) and shifts "backwards" (a broken cable would put the hub in LOW gear like the old Sturmey "X" hub, not high gear like the S-A AW, Shimano and SRAM's own T3). OLDs are 130 for freewheel and coaster, 135 for the disc brake version, and from the diagrams (I've not seen a real one, sorry) it appears there is not much scope for narrowing the OLD on these. The iM3 design doesn't not require any special tools for dis/re-assembly. The iMotion3 coaster version uses the historic Sachs Torpedo roller actuation brake.

    tcs
    Actually, you got that backwards. A broken cable will leave a Sturmey Archer in high gear, a Shimano in low.
    Gearhubs demystified and other cool stuff.


    Rule #12: The correct number of bikes to own is n+1

  6. #6
    tcs
    tcs is offline
    Palmer tcs's Avatar
    Join Date
    Mar 2007
    Location
    Parts unknown
    Posts
    4,144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dan Burkhart View Post
    Actually, you got that backwards.
    Nope, a broken cable will leave a Sturmey X in low, and a Sturmey AW and SRAM T3 in high, just as I said.

    Shimano? OK, I admit I haven't messed with one that was built in the last 30 years, and like Sheldon said, "Over the years the 333 hub was in production, Shimano made a number of revisions to the design in an attempt to make it more reliable. These revisions are not well documented..". I've even seen 'em with LH bell cranks.

    Best,
    tcs
    Last edited by tcs; 11-13-08 at 11:08 AM.
    "When man first set woman on two wheels with a pair of pedals, did he know, I wonder, that he had rent the veil of the harem in twain? A woman on a bicycle has all the world before her where to choose; she can go where she will, no man hindering." The Typewriter Girl, 1899.

    "Every so often a bird gets up and flies some place it's drawn to. I don't suppose it could tell you why, but it does it anyway." Ian Hibell, 1934-2008

  7. #7
    Senior member Dan Burkhart's Avatar
    Join Date
    Oct 2004
    Location
    Oakville Ontario
    Posts
    4,862
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by tcs View Post
    Nope, a broken cable will leave a Sturmey X in low, and a Sturmey AW and SRAM T3 in high, just as I said.

    Shimano? OK, I admit I haven't messed with one that was built in the last 30 years, and like Sheldon said, "Over the years the 333 hub was in production, Shimano made a number of revisions to the design in an attempt to make it more reliable. These revisions are not well documented..". I've even seen 'em with LH bell cranks.

    Best,
    tcs
    Ah yes, you refer to the early models with the indicator chain on the left side. In that case, you would be correct. As for Shimano, there may be some models I have not encountered, but every one I have seen, right up to the current models are shifted by means of a bell crank pushing a rod. Broken cable means rod springs out, low gear.
    Havn't run into a left side shifting one yet.
    And re-reading the post to which I responded, I see I missed part of what you said. Sorry about that.
    Gearhubs demystified and other cool stuff.


    Rule #12: The correct number of bikes to own is n+1

  8. #8
    F&S Dreigang Fan
    Join Date
    Apr 2009
    Location
    Germany
    My Bikes
    Hartje 3-speed
    Posts
    1
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I selected the i-MOTION T3 for my new bike after the old frame broke (fatally). I judged it to be the legitimate successor of the "Torpedo Dreigang", which has served me for over 30 years.

    I am now through 2 of these hubs. The first broke after 4 days. The second after a replacement from the dealer after 2 weeks of use - I became a little more careful. Contacted SRAM - the old facility in Germany - got immediate feedback and the request to return the bike though the dealer to them.

    Fixed after 3 weeks. Comment from SRAM: the axle broke because one bit of it was machined out of spec and not according to the drawing.

    Watch out - I would suspect that there are many more of these out there, waiting to break. Manufacture date around end of 2008, early 2009.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •