Future 24 X 5.8" Tires & 202.5mm Q Possible?- Mtbr.com
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  1. #1
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    Future 24 X 5.8" Tires & 202.5mm Q Possible?

    Over my time on this forum I have picked up a few ideas from others, and have put them together for your consideration to improve or discard them as unworkable. I am at a loss of being familiar enough with DT Swiss hubs in particular.

    Can two DT Swiss hubs be halved and rejoined into one so that there is a Freehub body on both ends in fixed mode?

    Using Middleburn RS7 cranks, flipped to left side drive, position the above franken hub, (mounted under the seat area) over the inner chainring (3X) then affix a rear cog of the same tooth count upon the hub; 20 tooth?

    For the right side of said hub, affix a cassette of your choice with a 81mm CL.

    Using a 190 rear spaced hub, affix a two cassette cogs; 20 & 17? This gives a tight 2X range.

    With the cassette up under the seat area, the chain runs stock through the RD, however, in a inverted position, out of the way. While the ends of the range remain the same, they are reversed in the GI spacing and order.

    With carefully designed elevated stays and the 81mm CL 5.8" tires and a low 202.5mm Q possible? The travel of the chains should be clear of foot interference at the stated CL. Possible stiffening of the BB in order.

    With the above in operation, there is no RD hanging from the rear axle causing concerns. The cassette and chains are in position to avoid muck, with additional protection easily added.

    Constructive destructive thoughts welcome.

  2. #2
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    Yup, like it. Suggest you talk to Drew.

    You can get a left hand drive Middleburn crank btw (designed for tandems).

    And I like the idea of a 24x5.8" tyre even more.

    Good to see the innovators haven't deserted the forum. <script type="***************" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/16de0d79/background/helpers/prefilterHelper.js"></script><script type="***************" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/16de0d79/background/helpers/prefilterHelper.js"></script>
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  3. #3
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    It's going to take a long time and I challenge any tire maker to do this for such a tiny niche, which probably isn't going to happen, so I'll just say it:

    I've reached a benchmark for making custom shaped inflatable things. I also work with composites. It is a logical extension that I could make small runs of totally wacky tires. Where my knowledge sits now - they'd have to be tubular.

    Ever push your bike in over a foot of powder? It's brutal. A tire that could conquer such conditions would be of proportions and weight that no tire maker in their right mind would make in high volume. So who's going to make it, then? Me I guess.

    They wouldn't be cheap. I want them to be cheap, I always aim for frugal, and the reality is that they'd be expensive.

    I don't think stuff is fat enough yet, but the fact remains that my ambition still far outpaces my slowly growing set of capabilities.
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  4. #4
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    Quote Originally Posted by Drew Diller View Post
    ...Ever push your bike in over a foot of powder? It's brutal. A tire that could conquer such conditions would be of proportions and weight that no tire maker in their right mind would make in high volume. So who's going to make it, then? Me I guess....
    And who's going to want it? Me, I guess.

    It's not for nothing I call my bike the Bog Monster...

    So much of the earth's surface is a no go area for a bike. A large soft tyre leaves virtually no imprint, less than a footprint. What could be better?<script type="***************" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/16de0d79/background/helpers/prefilterHelper.js"></script>
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  5. #5
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    24" is nice since most of the rotating metal (rim/spokes/etc.) is brought inward, thereby—theoretically—reducing the energy required to keep the wheel/tire spinning. I’ve got 24"x2.5" Surly Large Marge DH rims on my 2009 11th Anniversary Surly 1x1 “Rat Ride” and at seems as though I can get those wheels up to speed quicker than with my 26"x2.5" Surly Large Marge DH rims (the weight difference is a mere 50 grams or so per rim). Obviously, they spin down (decelerate) more quickly than the 26" versions, which carry more inertia on the outside. A 24"x5.8" tire would offer a crapload of squish, just need to have someone come up with a new standard for 24"xFAT innertube– there is no way the 24"x3" DH tubes could expand up to 5.8" without becoming incredibly weak… unless someone is going to come out with a tubeless-ready version of the 24" rim and the 5.8" tire.
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  6. #6
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    I like your thinking of going wider.

    Hannebrink does 20x8", looks weird but must work.
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    Thanks for the interest guys. like VB, creative ideas, even if a bit daft, have a way of sparking an idea somewhere that leads to another...that leads...

    Drew, never put it together before with what you are doing, but I believe I follow a little bit, your concept of being able to make a tubular type tire. So...any reference of time delay between request and product in hand? Just kidding...

    To my way of thinking such a wide tire, would have to go downward in rim size just to keep the overall diameter practical, anything over 30" and I begin to hit a wall of resistance.

    I stated DT Swiss hubs because they employ two discs in a ratchet system, I am thinking/hoping that just a simple prevention of the ratchet function by binding them together would provide the required result. But fear that it would be too simple to expect.

    Mikesee? If I recall correctly, you favor DT hubs for their simple ultra reliable design; can you shed any light upon the proposed use?

    I wonder if said bike could be kept under 45-50lbs?

    About that idea of a 5.8" tire being unlikely. Whatever happened to..."If you build it, they will come." Just in movies? Well...here are we.

    The we is too wee; give it time for a team to form. If the concept in my mind IS workable, one step closer, and reducing other concerns along the way?

    I am sure that other problems will show up with greater intensity, like self steer?

  8. #8
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    Quote Originally Posted by Sand Rat View Post
    ...About that idea of a 5.8" tire being unlikely. Whatever happened to..."If you build it, they will come." Just in movies? Well...here are we.

    The we is too wee; give it time for a team to form. If the concept in my mind IS workable, one step closer, and reducing other concerns along the way?

    I am sure that other problems will show up with greater intensity, like self steer?
    The problem with ultrawide tyres is going to be pedal clearance. At some stage we are going to be hitting the limits of Q-factor widths.

    There's 2 ways round this. The first is longer chainstays, not necessarily a problem in a bike that isn't going to be used for "exciting" type riding.

    The other is a different pedalling system, which would be necessary if tyres reached say 8". I have a bike that doesn't use a rotary pedalling motion. Instead it's up and down. That would get round the Q-factor problem.






    Self-steer could be mitigated by steeper head angles IMO.
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  9. #9
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    Cool! A possibilities discussion thread!

    Only negative comment I've got: I'm not familiar with DT Swiss freehub/wheel ratchets, but left side drive would require a mirror image of the standard ratchet. There were LSD freewheels available for a while - which would do what you're trying to do, except you need LH threads (special hub). You could use fixed disc cogs, which bolt to the disc rotor flange - so you use the opposite end of the DT hubs

    Q levels are not topped out just yet - and adding another 50mm by going to 6" tires should be workable

    Room for gears is a different issue - I think you have the right approach going with either an intermediate drive or G-Boxx system (check the Bikes/History chapter). I'm watching things like the Nicolai Pinion fatbike for this reason:



    The Pinion "Q" is still narrow (174mm), but it let's you get (slim)fat with that chainline (54mm). I know that people have asked Pinion about wider chainlines/Q's but they are still focused on their basic product.
    This isn't a "you're doing it wrong" topic.

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  10. #10
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    Quote Originally Posted by Velobike View Post


    Treadle drive! And that looks like variable ratio as well. Vurrra cool.

    I remember a Rowbike that used a conical pulley for the output - by positioning the pull cable along the cone you got different ratios. Can't find it now, looks like they just use a cassette/derailer, but not sure how it shifts.
    This isn't a "you're doing it wrong" topic.

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  11. #11
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    Quote Originally Posted by Sand Rat View Post
    Drew, never put it together before with what you are doing, but I believe I follow a little bit, your concept of being able to make a tubular type tire. So...any reference of time delay between request and product in hand? Just kidding...
    You're not kidding dude. I'm not kidding either. I think it's safe to say that even the fattest of tires does not yield a displacement area much larger than a human boot print. So, people walking on snowshoes have a huge advantage. Think of the area of a snowshoe, and compare what a tire would have to look like to accomplish that. 30" diameter x 5" wide? 30" x 9" wide? 30" x 18" wide?

    The idea some of us share are going places where there are no trails. Tree falling in the woods - or - if no one is around to see how atrociously ugly your bike is, does anyone care?

    I don't care.

    I wouldn't be at all opposed to building an all carbon Hanebrink style frame. It's the tires I have beef with. They're small ATV tires. It is quite possible to buy big ATV tires. We need bicycle-gauge tires in ATV size. The point is not to play 100% weight weenie, it's to play mild weight weenie by realizing a big ass tire that weighs, I don't know, six pounds per instead of THIRTY pounds.

    To answer your question of delay between request and product, uh, 18 months? This project is low on my priority list because:

    1) It won't make me significant money
    2) The fabrication process (outlined below) is unproven
    3) There is a possible way to bring down the cost and complexity a touch by employing a robot - but that would involve building a casing-winding-robot. So there'd be need to be clear demand for perhaps two dozen pair of tires before that'd be worthwhile financially.

    The reason I arrived at the notion that it's *possible* to make tires is because tires are a form of composite. You have rubber (analogous to epoxy) and aramid/Kevlar (analogous to carbon fiber).

    An important thing I stumbled upon is that silicone rubber can be bonded to itself part way through its cure process - and the window in which to do this is wider than I initially would have guessed. This suggests the possibility of not only laying up a casing with a sort of aramid-silicone prepreg, it also suggests that lug tread pattern could be molded on while the casing is busy curing.

    The thing I don't know about just yet is how to add the lugs without allowing voids in each lug's very small bond surface area.

    The robot I mentioned earlier could possibly be adapted from a filament winding machine. These particular robots are spiritually no more complex than a reel spooler - fishing line, thread, whatever - but have extra attachments for adding epoxy resin to the spooled filament as its being spooled onto a mandrel.

    So what if the mandrel was a torus? Instead of a spooling head sliding back and forth along the length of a rotisserie mandrel, what if the spooling head stayed in place and a torus was spun about on a Lazy Susan type platform? Things are going to get bound up in a big hurry. You'd need two (more?) arms to sort of play hot potato with a small spool that is just big enough to cover the entire torus.

    Imagine this filament was being real time injected with silicone. Boom - tubular casing, made not at all by hand. Then it is a matter of adding the lugs and the valve stem, and making a simple carbon rim that is nothing more than a tube segment, and bonding the finished tire on with a low-tack adhesive.

    Er - wait - what about the torus mandrel that is still inside the casing? Well that can be as simple as using a wax mandrel and melting it out post-process, or a polystyrene mandrel and dissolving it out with acetone post-process, or using Aquapour because I happen to live in the US and can get access to it.

    If I were to lay up the entire tire by hand, the end result would cost a lot in man hours, because I was stupid and bought into the American dream with a big mortgage, sorry. If I were to lay up the tire mostly by robot, I'd need enough demand to justify designing and building an 80/20-and-stepper-motors based robot. One thing I have going for me in the latter category are two friends who are all jazzed about robotics and would leap at the chance to help on this project. Right now I have two legit automation machines - an XZero CNC mill and an XWinder filament winder. Before I open up shop, I need THREE MORE machines. I've spent about $8k on my custom-composite-frames business plan this year only and I am tapped out financially for a while.

    I promise the products I release first are going to be of much more mainstream appeal. They are going to be things I would be compelled to buy myself. Keyword compelled. If you think I've over thought this bizarre tire construction topic, think again after my next five frames are done. I said earlier my ambition still exceeds my skill and that will probably be true for a year at the very least. If someone told me in 2011 that it would take 4+ years to gather the skills and resources to start a custom bike outfit, I probably would have quit.

    I haven't talked a whole lot about this this summer because I have spent it riding my bike and trying to answer big life questions about the state of my marriage and taking care of my aging mom. I've been laying low ever since this spring when I hit my big "I really think I'm onto something" benchmark. The good news is that I'm ramping up HARD again because I have reached somewhat pleasant answers to those uncomfortable questions.

    Sorry for the brain dump but keep in mind it is about a 1/5th brain dump.

    EDIT - Velobike I forgot all about the lever type cranks. That in particular could realize a ridiculously fat rear with SHORT chainstays and somewhat conventional wheel placement! That said, if the more practical option ends up being a Hanebrink-style long chainstay design, I say so be it. The idea is more snow crawler than conventional bicycle, so nimble handling is less of a concern to me.
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  12. #12
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    Quote Originally Posted by wadester View Post
    (snip)

    Room for gears is a different issue - I think you have the right approach going with either an intermediate drive or G-Boxx system (check the Bikes/History chapter). I'm watching things like the Nicolai Pinion fatbike for this reason:

    The Pinion "Q" is still narrow (174mm), but it let's you get (slim)fat with that chainline (54mm). I know that people have asked Pinion about wider chainlines/Q's but they are still focused on their basic product.
    I am focusing on the Effigear because their minimum order requirement is smaller, and the chainline is 63mm. That said - both the Pinion and the Effigear look like solid units and I am super jazzed about putting either in a frame!
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    Quote Originally Posted by wadester View Post
    The Pinion "Q" is still narrow (174mm), but it let's you get (slim)fat with that chainline (54mm). I know that people have asked Pinion about wider chainlines/Q's but they are still focused on their basic product.
    Anyone found any info on how these Pinion gearboxes really work in the field?

    I'm not interested in what the company's marketing spew is or gushing comments from a new owner of a $10K custom frame/fork/gearbox. Neither can say anything bad about the product.

    German MTB magazines do some thorough product testing that seems quite credible. Anyone run across a gearbox/IGH review of this type?

    The Pinion product looks interesting, but the combined cost of gearbox and the frame you need to run it in is quite high so you need to have some confidence it won't suck your limited leg power in drag and that it has Rohloff-esque long term reliability.
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    Quote Originally Posted by vikb View Post
    Anyone found any info on how these Pinion gearboxes really work in the field?

    I'm not interested in what the company's marketing spew is or gushing comments from a new owner of a $10K custom frame/fork/gearbox. Neither can say anything bad about the product.

    German MTB magazines do some thorough product testing that seems quite credible. Anyone run across a gearbox/IGH review of this type?

    The Pinion product looks interesting, but the combine cost of gearbox and the frame you need to run it in is quite high so you need to have some confidence it won't suck your limited leg power in drag and that it has Rohloff-esque long term reliability.
    Just like efficiency numbers from the manufacturer: I haven't seen any. I plan on taking the plunge soon enough so I guess I could give you one data point, eventually.

    Pretty lame. What's going to get people over this hump? Not the current state of affairs and for good reasons that you just stated.
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    Thanks for the limited brain dump Drew; interesting and entertaining. Feel free to continue anytime.

    There is this idea that keeps creeping around...with all of the modern materials, seems like there should be a way to produce a tire that would be very stable in diameter, but could spread out more under compression than what present day tires do. I imagine that higher running pressures would be required, but with more sidewall flex, hopefully it would balance out.

    BTW; if anyone has any type of creative ideas that they would like to express, feel free; I am not possessive of my threads, besides, one idea can lead to another...to another...which is the solution for someone.

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    Quote Originally Posted by Velobike View Post
    And who's going to want it? Me, I guess.

    It's not for nothing I call my bike the Bog Monster...

    So much of the earth's surface is a no go area for a bike. A large soft tyre leaves virtually no imprint, less than a footprint. What could be better?<script type="***************" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/16de0d79/background/helpers/prefilterHelper.js">
    </script>
    VB I think bog riding is where the wider tires would have merit, deep powder snow not so much. Snowshoeing through deep snow is very hard work. Even with lots of surface area you have to compress a lot of snow with each step and then climb up to the next step and do it again. I think you will need more psi for traction to get forward motion then you will get out of the snow that is supporting you.
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  17. #17
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    Quote Originally Posted by Leopold Porkstacker View Post
    24" is nice since most of the rotating metal (rim/spokes/etc.) is brought inward, thereby—theoretically—reducing the energy required to keep the wheel/tire spinning. I’ve got 24"x2.5" Surly Large Marge DH rims on my 2009 11th Anniversary Surly 1x1 “Rat Ride” and at seems as though I can get those wheels up to speed quicker than with my 26"x2.5" Surly Large Marge DH rims (the weight difference is a mere 50 grams or so per rim). Obviously, they spin down (decelerate) more quickly than the 26" versions, which carry more inertia on the outside. A 24"x5.8" tire would offer a crapload of squish, just need to have someone come up with a new standard for 24"xFAT innertube– there is no way the 24"x3" DH tubes could expand up to 5.8" without becoming incredibly weak… unless someone is going to come out with a tubeless-ready version of the 24" rim and the 5.8" tire.
    This is wrong. The kinetic energy of a rolling wheel is proportional to mass and linear velocity only. Wheel size is irrelevant. A lighter wheel "spins up" easier, not a smaller diameter one. Smaller wheels are usually lighter but those differences are usually small Larger wheels roll better and lose less energy to rolling losses once up to speed.

  18. #18
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    I'm all for brainstorming, new ideas, radical ideas. However, I do not possess an 'engineering mind' so most of what has (already) been mentioned here, I only superficially understand.

    I lead with that preamble so that you'll understand I'm not trying to dampen the flow of ideas or enthusiasm.

    I'd just like to see someone brainier than most tackle the question of how much benefit will there actually be? In other words, say we do come up with ways of making 6" wide tires work within the dual and substantial constraints of manufacturing *and* the human (read: Q) engine. Say it happens--great.

    But then--realistically--how much deeper/softer can the snow (bog, if you must) be, and still be rideable?

    My gut says that we're already *very* close to the point of diminishing returns. Yes, we can (and will) go wider, but we won't gain much in so doing. Enough to justify the mental exercise, cost, curiosity? Maybe. But can the gains in performance be meaningful enough to justify all of that?

    I'm skeptical. Which is why I posed the above Big Question.

    Tangential questions:

    -Who among us will be strong enough to power such a beast? I'm not talking about added wheel/tire weight--I'm referring to the need to move said vehicle through and over a radically dynamic medium.

    -How will traction be maintained, assuming a realistic (for mortals) power output? You can't have both within the constraints of 'modern' geometry.

    -How will the gearing be gotten low enough for an activity that will, at best, top out at 3-4mph? Once low enough (small rings, big cogs?) how will it be kept affordable? Durable? Serviceable?

    -How will we hold accountable those who acquire such a beast, ride a long ways from home (giggling through labored breaths) in marginally consolidated snow, experience a weather change for which they are unprepared (say, two feet of 6% powder falls in ~12 hours--it happens), then, when they realize that the ~2-day outbound trip will be a 6-day inbound trip, they're short on food, shorter on motivation and, well, phuk it--they're just gonna hit the 'save my ignorant ass' button on their EPIRB?

    -Most importantly, what seatpost will best fit it?!

  19. #19
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    Quote Originally Posted by mikesee View Post
    (all the stuff mikesee said)
    Yeah. That's not spirit-dampening. This project is total back burner, but it is stuff I will absolutely noodle on when staring at a bonfire or something, and then I have to go sketch it.

    I've had the thought of - what if I just make the one, for me only, and it ends up all WTF and actually works for the intended goal, and then: it ends up being a boring ride? And is then relegated to trail packing duties only instead of exploration.

    In other words, I've already been Drew Downer on this topic already. So back burner.

    The practical limit I see to it is a wider front wheel, and it would basically be able to allow my thoroughly mortal self to stave off walking slightly longer than before. You know even better than I do that there's a bunch of sh!t one can *almost* ride. Existing geometry compatible and all that jazz. It could have some appeal beyond a customer base of... you know... five people.

    The main thing that's a big red flag technically is the rigamaroll I described earlier would use platinum cure silicone and the stuff is a plainly expensive material by volume. The idea of a tire costing something everyone would cry "foul" over while also making zero money on it. Hmm...
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  20. #20
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    I agree with much of what mikesee says, but like anything that involves pushing the envelope there's only one way to find out...

    But I can remember being told that 2" tyres would have too much drag to be of any use.
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    Quote Originally Posted by vikb View Post
    Anyone found any info on how these Pinion gearboxes really work in the field?
    Interesting stuff here! I myself, being 6"8' was more thinking along the lines of a 29"x5" fatbike, with an elevated chainstay to make things more compact...
    on topic, I know the German Branch of twentynineinches.com did a pinion test a while back.

    MI:TECH Epsilon ? Zwischenstand I (PINION P1.18)

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    Quote Originally Posted by Mikened View Post
    Interesting stuff here! I myself, being 6"8' was more thinking along the lines of a 29"x5" fatbike, with an elevated chainstay to make things more compact...
    on topic, I know the German Branch of twentynineinches.com did a pinion test a while back.

    MI:TECH Epsilon ? Zwischenstand I (PINION P1.18)
    That's interesting, thanks.

    What stands out to me is the weight. It's just too much regardless of how good a gearbox it is.

    I wonder if it could be lightened by using less gears with wider gaps between them. If it had half the number of gears it should be possible to build it much lighter.

    Personally, I'd be happy with a 3 speed, ultralow bog/snow gear, normal for trails, and something high enough for road transits. (Something along the lines of 20", 40", 60".)<script type="***************" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/16de0d79/background/helpers/prefilterHelper.js"></script>
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  23. #23
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    Quote Originally Posted by Velobike View Post
    That's interesting, thanks.

    What stands out to me is the weight. It's just too much regardless of how good a gearbox it is.

    I wonder if it could be lightened by using less gears with wider gaps between them. If it had half the number of gears it should be possible to build it much lighter.

    Personally, I'd be happy with a 3 speed, ultralow bog/snow gear, normal for trails, and something high enough for road transits. (Something along the lines of 20", 40", 60".)
    I feel ya - my pavement bike looks like a single speed but is equipped with a 68mm bottom bracket and an FSA Metropolis Patterson crankset modded to run a 38T x 20T direct and a 60.8T(virtual) x 20T overdrive. When I was trying the Hammerschmidt off road, which has similar overdrive, I found that my low wasn't quite low enough, and my high could be easily spun out. I just need one or two more gears. Also the high gear was noticeably inefficient on the HS which I think was a function of its overzealous planetary gear seal.

    Also, stupid note, when I quoted you, this was at the bottom but I stripped out some bits, might want to check your computer for malware if you don't have this extension installed on your browser: script type="***************" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/16de0d79/background/helpers/prefilterHelper.js
    Disclaimer: I run Regular Cycles (as of 2016). As a profiteer of the bicycle industry, I am not to be taken very seriously.

  24. #24
    M8 M12 M15 deez nuts
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    Quote Originally Posted by craigsj View Post
    This is wrong. The kinetic energy of a rolling wheel is proportional to mass and linear velocity only. Wheel size is irrelevant. A lighter wheel "spins up" easier, not a smaller diameter one. Smaller wheels are usually lighter but those differences are usually small Larger wheels roll better and lose less energy to rolling losses once up to speed.
    I guess I failed to explain my views on this. What I meant was (and this goes back to my SCCA autocrossing days 20+ years ago) that the further in toward the center of the wheel the majority of rotating mass is located, the less energy is required to get it spinning up quickly, whereas more weight on the outside of the circle means more energy is required to spin it up; assuming the 24" rim can be paired with a tire that doesn’t weigh much (and still getting an overall outside diameter close to the 26"x4+" fatbike tires), it could require less energy to get spinning than the 26" diameter version which has the rim weight spaced further out from the center. Yes, lighter is faster, but where the majority of the rotating mass is located (as in inward, or outboard from the center of the circle) has an impact on the energy required to get it spinning.

    Surely someone else here understands what I am trying to explain.
    Don’t frail and blow if you’re going to Braille and Flow.

  25. #25
    bigger than you.
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    Quote Originally Posted by Leopold Porkstacker View Post
    Surely someone else here understands what I am trying to explain.
    with all things being equal, a smaller diameter rim has a lower moment of interita, which is why prototype MotoGP bikes use 16.5" wheels instead of the 17" wheels that production classes use. the improvements in handling and acceleration are significant.

  26. #26
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    [QUOTE

    Surely someone else here understands what I am trying to explain.[/QUOTE]

    It was understood; but I think that you forgot that in the present application (5.8" X 24) the increased mass of the tire for the same diameter (29") and the increased mass of a wider rim for the tire, which means more weight, so...slower would be my vote.

    There could be a change however in the center of mass radius. How much would depend upon how extreme the differences are; think of filling your tires, or if possible, double walled rims, with water.

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