From 27 speed to 9 speed - how?

L3BIUS
L3BIUS Posts: 91
edited December 2013 in MTB workshop & tech
Hey guys,

Currently on the stock setup on my GT Aggressor XC1 which is 27 gears.

I want to change this to 9 gears... but how do i go about doing this?

Any advice much appriciated!

Thanks
The New Beast GT Aggressor 2013 project

The Old Beast GT Aggressor Hardtail 2011 Custom Spec

Places i want to visit:
Gisburn Forest, Afan Forest, Holmbury Hill, Forest of Dean, Antur Stiniog, Fort William, Tweed Valley, Cwmcarn

Comments

  • Chunkers1980
    Chunkers1980 Posts: 8,035
    Remove two of the front rings and set front mech as a chain guide through moving stops in.
  • miceden
    miceden Posts: 225
    As Chunkers 1980 said... but... if you want a neater setup you can get single ring cranksets too
  • The Rookie
    The Rookie Posts: 27,812
    Or add a dedicated single ring to the existing crankset.

    Also the mech can be replaced by a number of different chain guide solutions.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • L3BIUS
    L3BIUS Posts: 91
    So nothing needs to be done at the rear wheel end? just the crankset and chain guide?

    Thast sweet :) thanks guys, much easier than i thought!
    The New Beast GT Aggressor 2013 project

    The Old Beast GT Aggressor Hardtail 2011 Custom Spec

    Places i want to visit:
    Gisburn Forest, Afan Forest, Holmbury Hill, Forest of Dean, Antur Stiniog, Fort William, Tweed Valley, Cwmcarn
  • L3BIUS
    L3BIUS Posts: 91
    Can anyone recomend a good chain guide to use instead of my front mech?
    The New Beast GT Aggressor 2013 project

    The Old Beast GT Aggressor Hardtail 2011 Custom Spec

    Places i want to visit:
    Gisburn Forest, Afan Forest, Holmbury Hill, Forest of Dean, Antur Stiniog, Fort William, Tweed Valley, Cwmcarn
  • cooldad
    cooldad Posts: 32,599
    Why not just use the mech until you know you get on with the single ring.
    I don't do smileys.

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  • jimothy78
    jimothy78 Posts: 1,407
    no-one's asked why you want to do it yet.
    If you're riding XC, then unless you're really fit, or live somewhere fairly flat, then isn't 1x9 likely to be a bit limiting?
  • Chunkers1980
    Chunkers1980 Posts: 8,035
    If it was flat he could be using the outside 42ish toothed ring. He only asked how to go to just 9 gears.
  • jimothy78
    jimothy78 Posts: 1,407
    Chunkers1980 wrote:
    If it was flat he could be using the outside 42ish toothed ring.

    True, but that doesn't detract from my question. I'm just curious why he wants to go 1x9 on an XC bike.
    If he's turning it into a commuter, fair enough; if he's turning it into an urban play-bike, fair enough; if he intends to use it on uplift-assisted gravity riding, fair enough... but in each case the build would probably be different.
  • The Rookie
    The Rookie Posts: 27,812
    L3BIUS wrote:
    Can anyone recomend a good chain guide to use instead of my front mech?
    All depends on ring size and usage, if you will be using a bash for example, then an inner guide ring or something like an n-gear jump stop is a good option, for more hardcore use you may want to consider an upper and lower element such as the superstar upper and stinger lower.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • L3BIUS
    L3BIUS Posts: 91
    I never use this as a commuter bike and use it purely for trail riding/light jumps and just general off road .. my previous one was single speed and i got along with it fine.. never wanted to get gears, but this one has 27.. i tend to stay on the smallest chainring and im happy with this.. I guess its just what i want to do!
    The New Beast GT Aggressor 2013 project

    The Old Beast GT Aggressor Hardtail 2011 Custom Spec

    Places i want to visit:
    Gisburn Forest, Afan Forest, Holmbury Hill, Forest of Dean, Antur Stiniog, Fort William, Tweed Valley, Cwmcarn
  • jimothy78
    jimothy78 Posts: 1,407
    L3BIUS wrote:
    I never use this as a commuter bike and use it purely for trail riding/light jumps and just general off road .. my previous one was single speed and i got along with it fine.. never wanted to get gears, but this one has 27.. i tend to stay on the smallest chainring and im happy with this.. I guess its just what i want to do!

    No problem with that, and if you've used singlespeed offroad, then yep, I'd consider you really fit.
    I don't think you really want to keep just an inner ring, though - it's going to be slightly limiting - the chainline won't be great from an inner position, and using the outer extreme of the cassette from there will not be ideal. Also, I don't think there are any top-guides made to work with rings smaller than about 32T (I may be wrong, but can't think of any), though you'll still be able to use a lower guide for a bit of security.
    Might be best to try a middle ring and see how you get on - what gear did you use when you had singlespeed? maybe try to aim for the equivalent gearing as that in gear 5 of 9, to allow yourself a bit of spread on either side?
  • L3BIUS
    L3BIUS Posts: 91
    Yeah i suppose i should try some other ways of riding first to see what the best set up will be, it may be that i go for the middle ring then! Cheers for your advice guys :)

    Also im not sure what gear my single speed was :S it was done when i bought it.. im sure i have the spec list somewhere though so ill find out!

    Cheers
    The New Beast GT Aggressor 2013 project

    The Old Beast GT Aggressor Hardtail 2011 Custom Spec

    Places i want to visit:
    Gisburn Forest, Afan Forest, Holmbury Hill, Forest of Dean, Antur Stiniog, Fort William, Tweed Valley, Cwmcarn
  • The Rookie
    The Rookie Posts: 27,812
    32:16 is the most common, which is the same front ring size as your middle ring and about the middle of the cassette at the rear.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • jimothy78
    jimothy78 Posts: 1,407
    I followed your signature link, then found your other pics of the same bike, and it looks like you were running 34/16 on your old bike. That's pretty high gearing, and I'm surprised that you've been mostly using the granny ring on your new one. (to put this in perspective, if you're using a standard 11-32 cassette then your old SS gearing would be the equivalent of using a 38T chainring with the middle (18T) sprocket. If your using an 11-34 cassette, then the middle chainring is 20T so the equivalent gearing would require a 42T chainring - that's big ring size).

    I think you really need to ride just using your existing middle ring for a bit and see how you get on. Then you can decide if you really want to go to single ring and if so, whether you want to size up or down from what you have.
  • Cqc
    Cqc Posts: 951
    Instead of buying a full chain guide that will cost £80+, what about this wide narrow ring from works components for 35?
    http://www.workscomponents.co.uk/works- ... -270-p.asp
  • The Rookie
    The Rookie Posts: 27,812
    Because they ideally need a damped rear mech which isn't available for 9 speed unless you use the Shimano/SRAM with cable spacer option.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • Cqc
    Cqc Posts: 951
    That's not true, I ride without a damped rear mech and have no issues, and I ride pretty rough terrain...
  • The Rookie
    The Rookie Posts: 27,812
    The word Ideally was used, that is true, some have found they work, others haven't........
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • Cqc
    Cqc Posts: 951
    That's true, but no one finds a top guide plus a narrow wide chainring to not be enough, which still adds up to less than the cost of a full chain guide
  • The Rookie
    The Rookie Posts: 27,812
    Cqc wrote:
    That's true, but no one finds a top guide plus a narrow wide chainring to not be enough, which still adds up to less than the cost of a full chain guide
    Well that's hardly surprising as many riders of 1x9 with conventional rings are only using an pure guide anyway!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • Cqc
    Cqc Posts: 951
    Yeah, so basically what I'm saying is dont buy a top and bottom guide!
  • The Rookie
    The Rookie Posts: 27,812
    Indeed, but some bikes have a habit of derailing when back-pedalling, even just enough to lift a pedal to pull away, others don't, so the fact yours doesn't is no proof one isn't needed!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.

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