Home Forums Bike Forum The 29Gnarr – Genius or insanity?

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  • The 29Gnarr – Genius or insanity?
  • buzz-lightyear
    Free Member

    The back wheel is on backwards and driven by an Alfine chainring up in the triangle, and a chain, all on the wrong side. The cranks drive the Alfine from the normal side via a short chain. So the disk brake mount has had to switch sides.

    In a nutshell: putting all the gearing gubbins in the middle of the bike.

    Wow!

    hugor
    Free Member

    Genius! All the gear changing benefits of the Alfine without the rotating weight.

    Junkyard
    Free Member

    if you look realy hard there is someone their without a stupid hat and without a beard kids just have the hats they dont count]

    Nicknoxx
    Free Member

    I’m not sure the weight gain of all the ‘gubbins’ will outweigh the benefits of having a better centre of gravity. The rotating mass thing’s a bit of a red herring IMO. But it’s an excellent attempt and I applaud their efforts.

    Nicknoxx
    Free Member

    CountZero
    Full Member

    Genius! All the gear changing benefits of the Alfine without the rotating weight.

    But there is no effective rotating weight; the hub is in the centre of the wheel, it’s big knobbly tyres that increase rotating weight.
    Nicolai put their gearbox in this position to decrease sprung weight(?); having a big heavy hub on a suspended rear wheel affects handling, so putting it into the centre of the bike re-establishes front/rear balance, and the same thing is probably what is intended with this bike, having the weight somewhere around the c/g.
    My take on it, anyway, I could easily be wrong, but it seems right.

    tracknicko
    Free Member

    more about weight balance for me rather than rotating.

    rode an alfine shod bike once and it was strange. manualled nice, bunny hopped lack a sack of crap.

    buzz-lightyear
    Free Member

    Countzero +1 IMO

    Sam
    Full Member

    Agree with CZ on all counts – lots of extra weight for no benefit. Nice execution of a wrongheaded idea though!

    stevemakin
    Full Member

    Ted has put it here so’s the weight is away from the back wheel for when its being jumped/tricked etc, makes sense when you talk to him, and he was still fabbing it at 4am on Friday morning, you’ve got too applaud someone like that who puts his ideas into practice.

    and of course the real new niche of the show was statement mustaches 😉

    ska-49
    Free Member

    Ive got some sketches of this idea from a few years ago !!
    The difference is that I had the disk fitted to the alfine, belt drive and mine was a 26”. I was going to have it built by Descendence bike but turned out be too complex. Wish I had. Looks lovely!

    Sam
    Full Member

    Fair enough Steve – that makes more sense – didn’t realise that was the intended application.

    brant
    Free Member

    Ted **** rocks

    ndg
    Free Member

    I wasn’t convinced by the 29Gnar, very heavy engineering to support the alfine, although I liked the concept. The bike for his Mum (white and yellow behind) was beautifully detailed though, as was the frame he had for his girlfriend (I think).

    buzz-lightyear
    Free Member

    Well I assume a production bike would accommodate the Alfine in the frame without all the hinge and bracket bits. Does it ride/pedal well though?

    takisawa2
    Full Member

    Why not just mount the hub in an oversize / custom BB shell & drive it directly ? Would need a beefed up interface for the “crank” bearings but that could be overcome…I think… 🙂

    10/10 though, I’m in aw of folk like him. Will 100% make the effort to go to the show next year.

    brakes
    Free Member

    too much torque at the cranks for an internal geared bottom bracket.
    I imagine the cost/ weight of one that was strong enough would be prohibitive.

    jameso
    Full Member

    He made his own rear hub for that bike from scratch with lathes and drills – no cnc – disc mounts both sides. Ted really does rule. The other bike on his stand was a beautifully detailed, clean-lined town bike he made for his mum. 2 bikes – one extreme to the other. Talented guy.

    ChunkyMTB
    Free Member

    I listened to Ted talking about some of the detail of the bike behind in that picture. Some of it was genius. Top bloke and a true engineer.

    ton
    Full Member

    looks terrible really tho dont it?

    martinxyz
    Free Member

    and it’s now 7 inches higher than the hub.

    miketually
    Free Member

    Would an EBB be a better way to tension the chainring-Alfine chain, and have a fixed Alfine rather than a sliding bracket?

    TooTall
    Free Member

    I thought he had engineered a very clever and involved solution for a problem that only sort of exists.

    For that I applaud him and his bike! 😀
    Up with this sort of thing.

    TiRed
    Full Member

    To be honest, it’s been done many times before. Google Rohloff hub as gearbox to see plenty of examples. Typically with FS bikes, where the hub tends to be hidden or better integrated into the frame.

    I don’t think it works with simple Ti tube profiles, personally. And I have an Alfine bike.

    julioflo
    Free Member

    I love stuff like this, in any discipline. It’s exploring the potentiality of a bike design rather than saying this is the way to do it. It’s not mainstream and does not profess to be. Good work chap.

    dja25
    Free Member

    Looks good imo, would like to see a closer look at in person. Couple more pics over on bike magic I see

    TheFlyingOx
    Full Member

    The back wheel is on backwards and driven by an Alfine chainring up in the triangle, and a chain, all on the wrong side. The cranks drive the Alfine from the normal side via a short chain. So the disk brake mount has had to switch sides.

    Forgive me for possibly being a bit clueless on this, but wouldn’t it have been a shitload less faffing about to just put the crank on the other side?

    miketually
    Free Member

    Forgive me for possibly being a bit clueless on this, but wouldn’t it have been a shitload less faffing about to just put the crank on the other side?

    Only if you don’t mind your pedals unscrewing 🙂

    ir_bandito
    Free Member

    Its nothing new though is it?

    Nicolai G-Boxx (the original was based on a (ohloff Speedhub) has the drive on the left, and the chain on the right.
    The Zerode has a Alfine hub mounted above the BB (with more conventional chain on the right)
    The Pinion is even available for hardtails…

    Don’t get me wrong, I think frame mounted gear-boxes are great, centreing the weight etc. And basing it on exisiting mass-produced equpiment will keep costs down. BUT, the Alfine (and original Rohloff-based G-Boxx) were designed for hub use so use epicyclic gears, so its not perfect.

    Pinion is by far the best idea as its designed specifically for a purpose. And its cheaper then the G-Boxx. (still bloomin’ pricey though)

    ir_bandito
    Free Member

    Forgive me for possibly being a bit clueless on this, but wouldn’t it have been a shitload less faffing about to just put the crank on the other side?

    Only if you don’t mind your pedals unscrewing

    Tandem cranks?

    miketually
    Free Member

    Nicolai G-Boxx (the original was based on a (ohloff Speedhub) has the drive on the left, and the chain on the right.

    Riding alongside someone with a Nicolai gearbox bike is odd, because the left-hand chain keeps moving when they freewheel; always seems really strange.

    ir_bandito
    Free Member

    In fact, why did Ted make his own hub? Why not use a fixed hub, and benefit from the freewheel integrated into the Alfine (like the G-Boxx)?

    miketually
    Free Member

    In fact, why did Ted make his own hub?

    Because he can? 🙂

    I think the hub is fixed; the description I read seemed to be saying it effectively had a 6-bolt disk mount on each side. Sure that a fixed-disk hub would have worked the same though? Maybe there’s potentially more force through the sprocket because of the gearing, so it needed a bolt-on sprocket?

    binners
    Full Member

    Dear god! WTF is wrong with you people? Would you like a shit-load of pointless, unsightly gubbins bunging up your frame, getting in the way, and being ground away by peak district mud?

    Or … OR…. how about this revolutionary concept….

    I know its going out on a limb, but I reckon it just might work 😉

    miketually
    Free Member

    You mean a slightly different bit of unsightly gubbins, in a more vulnerable location? 🙂

    ir_bandito
    Free Member

    being ground away by peak district mud

    ah, ‘cos derraileurs don’t just hang off the side of the bike, hitting rocks, getting ground up with gritstone grinding paste. But fully-sealed hub gears, especially ones mounted up in the frame are just daft for those conditions?

    😉

    binners
    Full Member

    Look where all that gubbins is though. Directly in line with all the crap being sprayed off the back tyre. Can you imagine what a peak district winter would do to that lot?

    You can tell its been designed by someone who lives in a place where it never rains 🙂

    ir_bandito
    Free Member

    mudguards? And besides, why should it be worse when its on the frame compared to in the wheel? Stop being a naysayer and pissing on new ideas.

    Back to my orignal thougts. Nicolai rear hub is suitably mental:

    binners
    Full Member

    So add a full set of mudguards to that lot?

    This bikes sure going to be a looker 😯

    rootes1
    Full Member

    that does indeed look like a solution in search of a problem. Also not very aesthetically pleasing…

    BUT good on him for trying it out – you never know might lead to a breakthough

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