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Dual hole 125/150 square taper (cotterless) cranks

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  • Dual hole 125/150 square taper (cotterless) cranks

    I recently bought a penny farthing from http://www.standardhighwheels.se. The specs for these bikes have been tweaked (improved) slightly and the website has not yet been updated to reflect that. So when the bike arrived one of the improvements was dual hole 125/150 square taper (cotterless) cranks. I was expecting only single hole 150mm cranks. In addition to the extra hole, they are nicely finished, handsome looking cranks.

    It immediately occurred to me that these would be pretty handy on a couple of unis that I regularly ride that still have this crank interface, including my 36" UDC Trainer/Titan. My plan had been to take them off the penny and transfer them but I sent a quick email to Per-Olof Kippel (who runs Standard Highwheels) and asked if he could sell me additional ones even though they are unlisted on their store.

    He confirmed that he could and that they intended to list them on the store in the future. For two sets of cranks (i.e. 4 individual cranks) he charged €64 (€32 per set) and €10 shipping (to Norway), which I think is pretty reasonable. Of course he might have given me a deal as a previous customer, so anyone else interested should confirm this price for themselves. From the invoice I was given the product code for these cranks appears to be "3133". I include a picture so you can see what they look like, for anyone else here who might be interested in upgrading their cranks on any unicycles they have that still use this interface.

    A set of dual whole SHW cotterless (square taper) cranks

  • #2
    hi thx!
    any comment on quality?
    the previous square tape dual hole where only the one for kids bike, which wear out r really fast in uni usage.
    have you idea of weight and material?

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    • #3
      I assume those are steel? Seems like UDC isn't making longer length aluminum square taper cranks anymore (or maybe they aren't making aluminum square taper cranks in any length? and just selling off remaining stock?). So even the single hole cranks would be of interest if they were aluminum.

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      • #4
        Weight and material? I must admit I did not check and I don't really want to remove them just to do so, when I shall have further sets arriving in a couple of days (making it unnecessary at that point). In person the colouring makes me think they are perhaps not steel and also a magnet does not seem to stick. I have fired off a question to Per-Olof to see what he has to say but I already know that he plans to be out of the office for a few days, so I might not get an immediate answer (by which time the new sets will likely have arrived).

        As for things like the strength, I seriously doubt they were designed/constructed for the kinds of abuse some unicyclists put on their cranks but then if you are intending to really abuse a unicycle, you would be far better off with an ISIS or Q-Axle hubs and crank combo anyway, since they are made for that purpose. Nonetheless, I am thinking that these would be handy for the likes of a 36", where they are less likely to be hammered and the usage would be closer to the penny-farthing the cranks were created for.

        What I can do when the new ones arrive, is to weigh them and take a picture of them next to the standard, basic steel cranks that my UDC Trainer came with (and perhaps one or two other cranks I have lying around) to get ideas about their thickness.

        I to have also noticed a lack of longer aluminium square cranks but they are not (yet) impossible to find. For example UDC Sweden still sells 152mm Venture cranks in Aluminium. I strongly suspect that you are right and this is just old stock. There is little incentive for UDC to make further aluminium square taper cranks as it provides one less incentive for people to upgrade to a more expensive ISIS based unicycle. I would guess the same is true for QU-AX, who have also produced aluminium square taper cranks. Though AFAIK, they never sold anything longer than 125mm aluminium square taper anyway.

        Whatever the material is, I had thought of suggesting to Per-Olof (and/or Roger Davies) that perhaps these cranks should be offered from sale on UDC websites, given they already seem to have a trading relationship. UDC pennies now use SHW (Standard Highwheel) tyres and they sell them as replacements on their website, but again there might be some reluctance from UDC given that, once again, it potentially undermines the desire for people to upgrade their uni to get hold of more interesting cranks.

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        • #5
          Per-Olof replied to me,

          aluminium alloy 6061, pair of cranks 360 grams
          360g is roughly 12&½oz, for the Americans out there.

          For comparison UDC UK states that "Kris Holm Spirit ISIS Disc Hub Cranks - 127/150mm" weigh 432g (≈15oz) or "Nimbus VCX+ ISIS Cranks - 100/125/150mm" weigh in at 454g (16oz). Single hole, 150mm "Nimbus VCX ISIS Cranks" are 490g (≈17&⅓oz)

          So yeah, at 360g they are very light for such long cranks!

          Now, obviously I am of course not trying to suggest these SHW cranks have anything like the strength of Spirit or VCX cranks but if you are more interested in the length or multi-hole capabilities than the pure strength/robustness, then they could still be interesting to some people here. Not least due to the lack of options for square taper as others have confirmed.
          Last edited by ruari; 2020-05-20, 09:57 PM.

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          • #6
            If Roger or someone else from UDC sees this, I do think they would be a nice option to offer from your websites but understand if you think it doesn't make business sense.

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            • #7

              Ok, here are four different square taper (cottterless) cranks I have to hand to allow some visual comparisons. I also weighed them myself as sets (i.e. combined weight of two cranks).

              From left to right: SHW (Alu) 125/150mm = 355g, Nimbus Venture (Alu) 125mm = 388g, Qu-Ax (Alu) 125mm = 343g, Unbranded (steel) 125mm = 676g



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              Oh and here is a bonus picture of them mounted on my 24" URC unicycle

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              • #8
                It is interesting to note that the Nimbus Venture is made out or 7075 Aluminum that is almost twice as strong and the 6061 that the SHW dual hole is made out of. The yield strength of the 7075 is 503 MPa compared to the 6061 at 276 MPa. Source.

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                • #9
                  That is interesting but where did you find that? It doesn't say the exact material on UDC UK for the original Venture "cotterless" cranks but the Venture 2 "cotterless" cranks are listed as 6061 T-6, as are the VCX "ISIS" cranks. Did they used to use 7075 on the original cranks and then move to 6061 T-6?

                  The cranks I noticed that are listed as using 7075 are Impact Groovy "ISIS" Cranks. Kris Holm Spirit "ISIS" Cranks states 7050.

                  EDIT: Actually, when I look on UDC US instead, I can find the original Venture cranks in ISIS configuration and they state, "Machined from 6000 aluminum" and then lower down say the material is 7075 T-6??

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                  Last edited by ruari; 2020-05-21, 06:45 AM.

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                  • #10
                    Possible discrepancies in materials for Venture cranks aside, the light weight, shape and construction would still leave me to believe that the SHW cranks are best viewed as a crank for light trails or road riding, where having multiple holes is still a benefit, depending on factors like the expected steepness of hills for the chosen route. If people expect to do hard muni or trials I think it is safe to presume they might have issues with these cranks. That said, anyone doing that would (should) be using ISIS or Q-Axle anyway. So I still think that the SHW cranks fill a certain niche.

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                    • #11
                      I think Nimbus venture cranks aren't very strong (based off an ISIS pair I have)


                      These dual hole cotterless cranks are very interesting, I haven't seen any others. I think I wouldnt hop on my cotterless unis though, I just use the unis to do normal riding. The 20's, 29 and 36 inch unis I have ISIS Cranks plus a 24" muni, it's just the standard 24 and 26" unis that I have cotterless cranks and it's not that important to change crank length on those.
                      Last edited by Gockie; 2020-05-21, 11:15 AM.
                      If you are female please join the “Female Unicyclists!” group on Facebook!

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                      • #12
                        Originally posted by Gockie View Post
                        I think Nimbus venture cranks aren't very strong (based off an ISIS pair I have).
                        Hmm... They seemed fairly well made to me but I guess I have never pushed them. Did you have issues with them?

                        EDIT: Also are you talking about the original Venture cranks, Venture 2 or Venture cranks X (a.k.a. VCX)?
                        Last edited by ruari; 2020-05-22, 12:29 PM.

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                        • #13
                          Originally posted by ruari View Post

                          Hmm... They seemed fairly well made to me but I guess I have never pushed them. Did you have issues with them?
                          I rode something like 20kms without the spacer and after that, they were always a bit loose, couldn’t be tightened well.
                          If you are female please join the “Female Unicyclists!” group on Facebook!

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                          • #14
                            Originally posted by ruari View Post

                            Hmm... They seemed fairly well made to me but I guess I have never pushed them. Did you have issues with them?
                            I rode something like 20kms on a 36er without the spacer and after that, they were always a bit loose, couldn’t be tightened well.
                            If you are female please join the “Female Unicyclists!” group on Facebook!

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                            • #15
                              Originally posted by Gockie View Post
                              20kms on a 36er without the spacer...
                              But, but... surely that is not supported and problems would then be expected?

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