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  • #31
    if its a sturmey made hub, isn't there a possibility that they might consider making a reasonably geared 3 speed uni hub or at least a reduced version of this, perhaps a 2:1.

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    • #32
      Originally posted by davejh View Post
      if its a sturmey made hub, isn't there a possibility that they might consider making a reasonably geared 3 speed uni hub or at least a reduced version of this, perhaps a 2:1.
      It's still a freewheel hub. Aside from a few people pushing the limits of unicycles it's not really a big market. Still, I wonder if the axle from this hub is at all compatible with the internals from another hub. I doubt it, but hmm...
      "A properly ridden unicycle is like an object in orbit: constantly falling but never landing." -Diogenes

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      • #33
        The only thing as far as i understand that would make a geared up single speed hub freewheel is the pawls. As there are no alternate gears, the pawls could be replaced with solid pieces which cannot disengage.

        Even if that was to happen there are 3 problems

        1: Backlash - this isn't a schlumpf and has not been designed in such a way that going backwards was even intended (although the internals are likely to be as strong backwards as forwards). The tolerances don't need to be tight because the hub is built to freewheel.

        2: One (high) gear isn't always good - Humi rexes are a nightmare to get going and dont have the rollover ability or stability that a larger wheel provides. They are only 1.5, if you went to 2+ you would end up with an uncontrollable dose of 'danger will robinson' meets 'pedal strike much' on any of the reasonable (small) wheel sizes. Put this thing on a 36er and it will feel like you have a 20kg wheel.

        3 Strength - I don't know exactly what stresses drift trikes take but I doubt they hop or ride roots and rocks. The 6 bolt connection to the frame looks great for lateral strength but a small drop could shear the bolts. On a trike, the riders weight is distributed more over the back wheels than the front whereas all of a unicyclists weight goes through the axle. Perhaps a lightweight rider who rides road only might be ok.

        Edit: by comparing the size of the bolts to the size of the axle, it looks like it uses M5 or 6 bolts. M5 is a saddle bolt, M6 is a seatpost or frame bolt. I wouldn't trust 6 of either of them sideways to survive any drop without shearing. Yes there is a support built into the hub body but that would not help much.

        Sunrace (sturmey) by making these have shown that they are interested in making bits for fringe sports. Drift trikes may be riding a bit of a popularity wave atm but the market for the hubs may well be as small as the geared uni market.
        Last edited by davejh; 2014-03-19, 11:49 PM.

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        • #34
          Originally posted by davejh View Post
          Drift trikes may be riding a bit of a popularity wave atm but the market for the hubs may well be as small as the geared uni market.
          I dunno about you guys, but I reckon I would be way more interested in a geared unicycle if I could afford it. Not saying anything bad towards the guy who makes Schlumpf's, I know he's a one-man show, but adding £900 to the price of a unicycle to go a little faster is unfeasable for a lot of people. I'd be willing to bet the market for a geared uni hub is far greater than what you see at the moment because the price is so prohibitive
          “It is well known that a vital ingredient of success is not knowing that what you're attempting can't be done. A person ignorant of the possibility of failure can be a half-brick in the path of the bicycle of history.”

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          • #35
            These are available for pre-order now for £295, paypal sales@jrdrifttrikes.com. I just put in my pre-order.

            £295 for complete built wheel, forks and custom rotor. You'll need to pre-pay then wait until these are ready. Our tight budget wont let us get these made until we've sold some!

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            • #36
              Wow, a whole front end with a wheel for only 295GBP, i feel I'm going to be able to afford a geared hub pretty soon
              Last edited by stilkus; 2014-04-09, 10:40 AM.

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              • #37
                Finally got this delivered and built it into a unicycle. I still need to adjust the brake. The rotor is a custom 225mm Hope and the largest cranks I can put on are 125mm. I didn't get much time to practice with it yet, maybe 20-25 minutes in which time I was able to do about a half revolution. I'm guessing it will me take a few weeks to be able to ride this on flat ground.

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                • #38
                  Amazing! Looking forward to videos!
                  "I'm a unicyclist. I make my own reality."

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                  • #39
                    Subscribed.
                    "I used to watch Highway Patrol whittlin' with my knife..." - NY

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                    • #40
                      Originally posted by waaalrus View Post
                      Finally got this delivered and built it into a unicycle.
                      What is the wheelsize, 20 inch? That would be 76 virtual inches. You would have about the same leverage as with 59 mm cranks on a 36 inch. This must be difficult to ride indeed. And the wheel looks so innocent.

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                      • #41
                        60rpm -> 14mph !
                        Its gear inches is large relative to unicycles, but compared to bikes, is not that abnormal. Riding on flat ground sounds viable in my opinion. Looking forward to see you riding this!

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                        • #42
                          Originally posted by LanceB View Post
                          Amazing! Looking forward to videos!
                          When I get this down I'll probably shoot a video in the same location as this one:

                          [ame="http://www.youtube.com/watch?v=W2r-cfwSDRk"]Freewheel unicycling on Santa Barbara Road 6-23-2013 - YouTube[/ame]

                          It will be mostly the same except for less pedaling. I don't know a way to make an interesting sidewalk video.

                          Originally posted by Klaas Bil View Post
                          What is the wheelsize, 20 inch? That would be 76 virtual inches. You would have about the same leverage as with 59 mm cranks on a 36 inch. This must be difficult to ride indeed. And the wheel looks so innocent.
                          Yes, it's a 20 inch wheel and the tricky part for me is to learn more of skate start where I push with one foot and coast for a little while before pedaling.

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                          • #43
                            Nice gear-inches... Is there any particular reason for the 125mm crank limit? Is it purely because of the wheel size?

                            Can't wait to see some speed-tests on it once you get the hang of it!
                            “It is well known that a vital ingredient of success is not knowing that what you're attempting can't be done. A person ignorant of the possibility of failure can be a half-brick in the path of the bicycle of history.”

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                            • #44
                              Really looking forward to seeing it in action.

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                              • #45
                                Originally posted by Piece Maker View Post
                                Nice gear-inches... Is there any particular reason for the 125mm crank limit? Is it purely because of the wheel size?

                                Can't wait to see some speed-tests on it once you get the hang of it!
                                Well, zero Q cranks larger than that will hit the "frame" because of the design:



                                I'm going to check to see whether my 135mm Sinz cranks have enough Q factor to clear the frame.

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