Cassette questions

apple eater
apple eater Posts: 302
edited May 2013 in MTB workshop & tech
My bike is a hardtail carrera vulcan from 2011. It should have and 8 gear cassette but the previous owner has either changed it to 7 or thrown out the 8th gear.

I'm now wanting to put an 8 speed cassettte back on. i have a shimano m 475 hub on the back which is wearing very well so i'm sticking with it until it finally packs up.

Is there a certain type of cassette i need or in the 8 speed bracket they are all pretty much basic and standard fit? What is the difference between 30 / 32 / 34 teeth on the largest cog, in terms of effort / ease of pedalling etc ? They seem to only have 11 teeth on the smallest cog.

Any recommendations?
I don't know enough to make smart r's remarks about peoples choice of parts 'n' things, yet!

Comments

  • cooldad
    cooldad Posts: 32,599
    Any 8 speed will work. Bigger cogs, lower gear, and slightly bigger jumps between ratios.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

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    Parktools
  • Buckled_Rims
    Buckled_Rims Posts: 1,648
    Most Shimano type 8 speed cassettes will fit, they are pretty cheap if you look around the internet (£9.99 from CRC). You should NOT really use the big front ring with the big rear cog - it's called cross chaining and it's a bit naughty. It'll twist and rub against the chain and cogs. Likewise, the small front ring should not be used with the small rear cog. For the most efficient use try the middle cogs on the rear cassette, this keeps the chainline straightish.

    There is a big difference between 30t and 34t on rear using the small front ring. 34t will make you be able to climb steep sections, but by peddling fast (but moving very slowly). As for the 11t you will rarely use that, I probably don't use mine for about 99.95% of the time.

    If you are unsure, go for a 11-34 and get a new chain fitted. The old chain might (most probably will) wear out a new cassette prematurely.
    CAAD9
    Kona Jake the Snake
    Merlin Malt 4
  • The Rookie
    The Rookie Posts: 27,812
    1-34 is not commonly available in 8speed (if at all), so you have a choice of 11-30 or 11-32, the difference is minimal on either to be honest.

    I have a couple of useable 8speeds, PM me if you want one cheap.
    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.
  • mister p
    mister p Posts: 405
    1-34 is not commonly available in 8speed (if at all).

    CS-HG41 8 speed is available in 11-30, 11-32 and 11-34 combinations, see WIGGLE HERE
  • zx6man
    zx6man Posts: 1,092
    Original is a SRAM PGM 830 or 850 I think. Can check tonight and post it if ya need to know.
  • cooldad
    cooldad Posts: 32,599
    Makes no difference what the original was - any Shimano or Sram 8 speed will work.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • zx6man
    zx6man Posts: 1,092
    cooldad wrote:
    Makes no difference what the original was - any Shimano or Sram 8 speed will work.

    I know, just in case the orginal spec was required really with it being changed to something dodgy.
  • supersonic
    supersonic Posts: 82,708
    1-34 is not available in owt ;-)
  • apple eater
    apple eater Posts: 302
    So if i go for the HG 8 speed cassette with the ratio's 11 - 32 they will be the same as my sons bike which i find comfortable to ride, gears wise.

    It is recommended on the wiggle link ^^^ up there, that i should use a HG chain. Anyone have a different recommendation for the chain or is it just a case of at this end of the scale choice is limited?
    I don't know enough to make smart r's remarks about peoples choice of parts 'n' things, yet!
  • cooldad
    cooldad Posts: 32,599
    KMC 8 speed. Whatever the cheapest you can find.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • supersonic
    supersonic Posts: 82,708
    Any 8 speed chain will be fine, SRAM chains are good kit.

    11-32 will be the same range, but the steps in the middle may be different. And gearing depends on the front chainring size, and wheel size too.
  • apple eater
    apple eater Posts: 302
    next question.

    7speed shimano cassette and the lockring has 12 teeth grooves in it but when i look at park tools for the part i need they list them as sr-1 and fr-1 compatible.

    What does this mean and how do i identify which one i need?
    I don't know enough to make smart r's remarks about peoples choice of parts 'n' things, yet!
  • supersonic
    supersonic Posts: 82,708
    I don't understand the question - why a seven speed cassette? What part do you need?
  • supersonic
    supersonic Posts: 82,708
    Ah, you mean the tools to remove? Cassette remover, not a freehweel remover. Also need a chainwhip.

    http://www.ebay.co.uk/itm/Icetoolz-Cass ... vi-content