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  • 81 gears?
  • jackthedog
    Free Member

    Anyone know why such a hub would exist?

    Posted 12 years ago
    RealMan
    Free Member

    How do you get 81? Single ring up front, 9 speed cassette, so its same as 3×9? Which is 27.

    Posted 12 years ago
    julianwilson
    Free Member

    RealMan – Member

    How do you get 81?

    three rings up front. 3x3x9=81.

    Sheldon did it ages ago btw, albeit with a smaller cassette. He seemed to suggest it was a bit pointless.

    [eidt] Here it is: http://sheldonbrown.com/otb.html#63speed

    Posted 12 years ago
    jackthedog
    Free Member

    Unless you run a triple up front!

    Is that the point then – to do away with triple rings?

    Posted 12 years ago
    Militant_biker
    Full Member

    The Cycles Maximus trikes (the ones that some cycle taxis, and parcel carrying couriers use) have a similar setup, although I think they have just 2 rings at the front.

    You can achieve a stupidly low gearing which is essential for getting heavy loads up steep hills. I occasionally used to deliver bundles of newspapers to shops and newsagents, and was glad to have a super wide range of gears.

    Posted 12 years ago
    epicyclo
    Full Member

    jackthedog – Member
    Anyone know why such a hub would exist?

    Folding bikes. Front derailleurs can be impossible to fit on some.

    Problem solved by using a 3 speed hub with an ordinary rear derailleur.

    Anyway how about 16X14 = 224 ratios?

    One of these (Cambiogear 16 speed front ring) with a Rohloff.

    Posted 12 years ago
    jackthedog
    Free Member

    The Cycles Maximus trikes (the ones that some cycle taxis, and parcel carrying couriers use) have a similar setup, although I think they have just 2 rings at the front.

    Ah, interesting. Useful for cargo bikes then.

    Folding bikes. Front derailleurs can be impossible to fit on some.

    Problem solved by using a 3 speed hub with an ordinary rear derailleur.

    Ah, okay.

    Anyway how about 16X14 = 224 ratios?

    Ha, nice. Think we could bodge a Cambiogear jobby to a Hammerschmidt + sturmey 3 speed with 9 speed cassette?

    3x9x2x16 = 864 ratios?

    Posted 12 years ago
    maccruiskeen
    Full Member

    Or you could use a NuVinci hub and have an infinite number if ratios, or a NuVinci and a triple up front and have 3x infinity. Or a triple on a hammershmit and have 2x3xinfinity

    Posted 12 years ago
    james
    Free Member

    I feel like I’m missing something, why won’t a 10spd casette fit onto that hub for 90 gear ratios?

    front mech will deal with a 22T difference? 11-36T 10spd casette + the 3spd hub would give a fair range?

    Posted 12 years ago
    epicyclo
    Full Member

    jackthedog – Member
    ‘Anyway how about 16X14 = 224 ratios?’
    Ha, nice. Think we could bodge a Cambiogear jobby to a Hammerschmidt + sturmey 3 speed with 9 speed cassette?

    3x9x2x16 = 864 ratios?

    That would give the gearie boys a few things to twiddle with when they’re riding. 🙂

    Posted 12 years ago
    Orange-Crush
    Free Member

    I’m sure the 3 or 4 speed hub with a two speed derailleur was not uncommon in the Fifties (from the pictures I have seen).

    Posted 12 years ago
    crazy-legs
    Full Member

    Probably 15 years ago some bloke brought a bike into the shop I worked in going on and on and bloody on about how he’d customised it to give 75 gears. It was done on the same principle, hub gear bodged with a cassette.

    All we could think of was “WHY?”
    It was one of those weirdy-beardy types who can never just make do with off-the shelf, always felt the need to customise and bodge, not because it was better, just to be different.

    Posted 12 years ago
    molgrips
    Free Member

    Whatever happened to those NuVinci things? Can you buy one yet?

    Posted 12 years ago
    jackthedog
    Free Member

    I feel like I’m missing something, why won’t a 10spd casette fit onto that hub for 90 gear ratios?

    Can you run 10 speed with a triple up front? I assumed not, which is why I didn’t originally mention it, although that now seems like a ridiculously insignificant compatibility concern after the idea of bodging together a Cambiogear and a Hammerschmidt came up.

    Posted 12 years ago
    jackthedog
    Free Member

    It was one of those weirdy-beardy types who can never just make do with off-the shelf, always felt the need to customise and bodge, not because it was better, just to be different.

    I know that sort. The chap I’m thinking of was welding together some hideous cargo trike abhorrence the last time I spoke to him.

    Posted 12 years ago
    TheBrick
    Free Member

    I like the idea of this hub. Will be nice to see how it performs

    Posted 12 years ago
    edhornby
    Full Member

    I can’t see the point myself,

    derailleurs give you lots of gears and light weight but the swingarms are prone to strike and mud clag

    hubs are good for chain route and simplicity but are heavy over the axle and not as many gears

    this ‘solution’ is the weight in the wrong place with a swingarm. worst of both bits..

    Posted 12 years ago
    epicyclo
    Full Member

    crazy-legs – Member
    …It was one of those weirdy-beardy types…

    One of those stares out my mirror every morning. One of these days I’m going to shave him…

    Orange Crush – Member
    I’m sure the 3 or 4 speed hub with a two speed derailleur was not uncommon in the Fifties (from the pictures I have seen).

    Yes. I’ve got one, needless to say (weirdy-beardy). Basically it was 2 cogs threading onto an adapter that fitted where the normal single cog went. I can stick a pic up in the unlikely event that there is anyone interested.

    Edit:

    I’ve just thought of a good application for that hub. On the back of a fatbike. 2 chainrings and 2 cassette type cogs like a dingle speed – no derailleur needed. That would allow one 2 set of 3 speed ratios to be ultra low for very soft going, and the other for normal going, eg 24F/23R and 32F/15R. Much lighter than an Alfine and good range.

    Another edit:

    Max rear allowed is 34T, so you could have 22F/32R and 32F/22R which gives a very wide range.

    Posted 12 years ago
    james
    Free Member

    “Can you run 10 speed with a triple up front? I assumed not”
    Shimano offer 3×10, though in 24-32-42, an 18T range
    IIRC SRAM are also offering 10spd compatible triple chainsets

    Posted 12 years ago
    TiRed
    Full Member

    SRAM have been making 3×7 for years. Was mainly the preserve of folding bikes, recumbents and cargo bikes. I’m surprised that Sturmey Archer have taken so long to catch up.

    Posted 12 years ago
    epicyclo
    Full Member

    I can’t help thinking that combining a derailleur with a hubgear gets you the worst of both worlds.

    Posted 12 years ago
    maccruiskeen
    Full Member

    Whatever happened to those NuVinci things? Can you buy one yet?

    Yes

    A friend of mine was supposed to be getting a couple of dozen hubs to evaluate, might check if needs any help with that evaluation

    Posted 12 years ago
    molgrips
    Free Member

    Hmm, Nuvinci seems really cheap compared to Rohloff…

    EDIT: Holy cow!

    “The latest N360 model weighs approximately 2450 grams..”

    Posted 12 years ago
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