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  • Three Speed MTB Hub Gear – Update
  • oliverdavey80
    Free Member

    Last summer I posted about a modified 3-speed Sturmey Archer hub that I’d had machined to accept cartridge bearings in a bid to make it more suitable for off-road use. You can read that post here:

    http://singletrackworld.com/forum/topic/three-speed-mtb-hub-gear

    I’ve been running it on my mountain bike ever since and so I thought some people might like an update. In short, so far it hasn’t put a foot wrong. It’s still spinning and shifting smoothly despite being dragged through the winter gloop. A young family has meant relatively limited time on the bike though, so I’ve just had a second hub made. This new hub has gone on to my commuter / road bike, so while it may not see as much mud it will be doing much bigger mileage. Hopefully, if the hub does have any issues that need ironing out, this will help to flag them up that much faster.

    This time, rather than using bespoke, aluminium top hat axle bearing seats, I’ve used the original steel axle bearing cones and covers. These have been machined to accept cartridge bearings and now provide an extra layer of defence against the elements and a stronger, more positive thread. The original aluminium ones haven’t caused any issues, but they just seemed like any unnecessary layer of complication when the originals can be modified to do the same job.

    Below are a couple of photos of the bike and the hub (which now almost looks stock from the outside). I have put together a small website mainly for my own amusement, but if you’d like to know a bit more about the hub then feel free to have a look here http://www.daveypushbikes.com while further details about the bike can be found here http://www.daveypushbikes.com/blog.

    [/url]Pinnacle Arkose Sturmey Archer 3 Speed by Oli Davey, on Flickr[/img]

    [/url]Pinnacle Arkose Sturmey Archer 3 Speed by Oli Davey, on Flickr[/img]

    Edric64
    Free Member

    That looks very interesting .Love a bit of engineering !!

    opusone
    Free Member

    How does it feel to ride? I’ve got an alfine on my commuter and considered getting a hub geared mtb but people said it makes the back end feel really leaden / planted in the ground.

    TurnerGuy
    Free Member

    Kickstarter it…

    Andy-R
    Full Member

    I missed the original thread but I’ve just had a look through it now – I’m someone else who’s had similar thoughts re. 3 speed hubs, in other words, all the good bits of a singlespeed but with a slightly lower bail-out gear and something a bit higher for occasional flatter sections. To be honest, as 95% of the time I more than manage around here on a singlespeed, I don’t need much more than that.
    And dérailleur systems don’t like lots of heather, branches and other assorted crap. That’s what a lot of my riding is like.

    I’ve got an 8 speed Alfine hub geared bike, which has been faultless in its operation but I don’t like the spongy engagement feel – I tend to “ratchet” more than some people, especially in tight, slow trialsy stuff and a fast engagement hub is pretty much essential for that. Well, for me anyway.

    teamslug
    Free Member

    Love the idea, My commute is off road but relatively flat. Would be great and 3 gears would be more than enough. Be a great idea to save the more expensive drivetrain parts.

    thepodge
    Free Member

    I enjoyed my Alfine offroad but ended up going back to standard gears as my new frame is a 142 back end, thinking of putting it on the commuter but 8 gears is a total overkill for that so a 3 speed would be ideal.

    amedias
    Free Member

    so OP, now the question is, how much are you going to charge all us interested people to modify our hubs? 😉

    On a side note, has anyone got much experience of the 5 and 8 speed Sturmeys? been looking at them recently but don’t know anyone with first hand experience.

    soulwood
    Free Member

    Interesting, although I remember my 3 SPD SA from my Raleigh Bomber had 1 & 2 quite close but 3rd was seemingly another planet away in difference. Couldn’t wait to use derailleur gears after slipping and grinding SA gears. Have they made them better in terms of gearing and better shifting? Is the crappy toggle chain no more?

    oliverdavey80
    Free Member

    I’ve got both 8 and 11 speed Alfine hubs that have been on the back of my mountain bikes over the years. The 8 speed needed two new sets of internals in the first 18 months that I had it and eventually the bearing cups started to ovalise in the hub shell (which can’t be purchased without buying a whole new hub). The 11 speed was a bit better, although seemed to loose oil like an old British motorbike. Both hubs suffered from a rather spongey feel at the pedal. This is just the result of how they work – in very simple terms they are just a number of 3 speed hubs connected in series (hence the greater inefficiencies). They are also both relatively heavy things, and my current 3 speed hub saves me around 0.75kg by comparison.

    I still haven’t ridden any hub gear whose shifting can match the smoothness of a good derailleur set-up. Because of this I see hub gears as being more like a selection of single speeds – once you’re in a gear that you like you tend to stick with it rather than constantly trying to maintain a perfect cadence (if this sounds like you then a hub gear probably won’t be your thing). So having lots of relatively closely spaced gears isn’t really as much use as it could be. That’s what really got me thinking about a three speed hub – just enough for going up, along and down – as I’m simply not strong enough (or can spin my legs fast enough) to use a single speed for the types of riding I want to do.

    According to Sturmey Archer the hub has an overall gear range of 177% and gear steps of 33%. I find the easiest way to think of it is that the hub has a direct drive (1:1) along with an over-drive gear (3:4) and an under-drive gear (4:3).

    burko73
    Full Member

    Does it come with an old grifter twist grip or a chopper style gearlever…?

    My on one fatty would look good with a ball catcher gearstick between the top tubes… 😆

    nickjb
    Free Member

    …or a chopper style gearlever…?

    Still got this in the spares box waiting for a project. It has an amazing ‘click’ on the indexing.

    Speeder
    Full Member

    I hate to be a pedant as I love the idea of a simple 3 speed bike but that’s not an MTB.

    TurnerGuy
    Free Member

    but that’s not an MTB.

    keep up – that’s his commuter / road bike – the mtb bike is on the thread he linked to.

    thisisnotaspoon
    Free Member

    Ohh I like that, a lot!

    I was debating hub gears for my tourer/commuter, but ultimately opted for normal (3×9) gears because it’s the chain that wears out/needs maintenance, and putoline wax pretty much makes that a non-occurrence. By my estimate I’ll probably lube it 4x a year, and that’s assuming I do 2000miles on it and actually use it in the rain rather than drive. In reality I reckon I’ll do it once or twice a year!

    Which light is that? I keep looking at dynamo lights and the supernova ones certainly look the most ‘metal’. Tossup then between the “road legal” and “race” versions. I quite like the idea of the race one dimming below 8mph for town use, then automatically kicking in when the pace picks up.

    dvatcmark
    Free Member

    Did SRAM make a 3 speed MTB rear hub for a short period of time or am I remembering wrong?

    thisisnotaspoon
    Free Member

    They do (i3 and i9), I though they also made one with a freehub, think it was 3x, you could use it with a cassette to as a replacement for a front mech. But cant find it now.

    no_eyed_deer
    Free Member

    Slipping/grinding gears occur with poorly-adjusted cable tension and/or lack of cable-chain-shifter lubrication. SA hub gear engagement is very sensitive to cable position. If mine is mal-adjusted by as little as 2mm in the cable it will happily grind gears, especially under high load.

    SA 3 speeds – I love ’em! 😎

    oliverdavey80
    Free Member

    The front and rear lights are indeed made by Supernova, and very lovely they are too. I’m running them off an SP Dynamo front hub – they seem to have come up with a rather clever arrangement of magnetics which a number of other companies license (who all seem to charge more for the privilege).

    Shimano, Sram and Sturmey Archer all make 3 speed hubs in 135mm OLD spacing with a disc brake mount, although I’m not sure whether any of them are officially rated for off-road use. I started with the SA hub because they have the largest range of shifter options and the best spare parts support.

    I suppose that SA hubs can be a bit sensitive to cable adjustment. But then in my experience if you unscrew a barrel adjuster on a rear derailleur by a couple of millimetres it would also start causing some problems.

    mick_r
    Full Member

    I’ve got one of those hubs in a 29er wheel – soon to be re-homed into a new frame…..

    I’m currently building this frame for local CX races (design is only OK for regional stuff – must make a “Not UCI Legal” sticker). Having watched at least 10 rear mechs snap off in the mud of the final NWCCA round, I’m making this as uncloggable as possible (hence a carbon 29er fork and Sturmey hub). Cables will run straight in the front of top tubes and pop out in just the right places for Sturmey / rear disc.

    The only bit I’m not liking with the SA is the loose cable in 3rd gear can jangle against the stay (running with SA thumbshifter).

    Hub has currently been great for mtb but I’d be most interested in having it improved before winter.

    thebees
    Free Member

    Great work ! I think one of the big advantages of not having a derailleur would be that you could produce an enclosed drivetrain cover which would be fantastic for the British winter. Twenty minutes into a ride at Swinley, even at this time of year, and my chain is grinding horribly.
    Surely I’m not the only one who’s sick of scrubbing drivetrains with a little brush after every ride !

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