11 - 30 cassette

richard36
richard36 Posts: 346
edited January 2017 in Road buying advice
Hi

Would appreciate some advice/help.

I have an old 8 speed road bike. I need to change the rear wheel and thought I would change the cassette and chain at the same time. At the moment the bike has a triple ring at the front and a 13 - 26 cassette at the back. Wiggle are selling a Shimano CS HG41 8 speed cassette and the 2 options are 11 - 30 and 11- 34. I've managed okay with the cassette I've got and knowing next to nothing about gear ratios wondered which of the above 2 I should go for. From what I've read the 11 - 34 would be good if I struggled up steep hills but I don't so shall I go for the 11 - 30 or is there little difference between the 2?

Many thanks

Comments

  • itboffin
    itboffin Posts: 20,072
    I'm not sure the 8 speed groupset can accommodate an 11-34 cassette, what gearing does the triple have?

    The smallest is most likely already very low 20s so you end up with an insanely small gear even with a 30t cassette
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  • cycleclinic
    cycleclinic Posts: 6,865
    you will need an old long cage mtb mech to make an 11-34T work.

    anything less than 1:1 on a road bike is pointless. you would be better of walking as you will be travelling so sloly you fall off anyway or the front wheel rises up and you land on your back.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • germcevoy
    germcevoy Posts: 414
    SRAM do a PG850 in an 11-28. That would be more than enough for a triple setup. Your smallest ring at the front probably isn't any bigger than 30 teeth. Pair that with a 28 at the back and you'll be able to get up anything.
  • richard36
    richard36 Posts: 346
    Thanks for the replies

    I've just noticed on Wiggle that they have a Shimano HG50 cassette with the following options 12 - 23, 12 - 25, 13 - 23 and 13 - 26. Given that my existing cassette is 13 - 26 then I could go for a direct replacement or would one of the others be a better option [I don't need any more 'help' to get up hills but perhaps could do with 'help' to go faster downhills]

    Thanks
  • germcevoy
    germcevoy Posts: 414
    Richard36 wrote:
    Thanks for the replies

    I've just noticed on Wiggle that they have a Shimano HG50 cassette with the following options 12 - 23, 12 - 25, 13 - 23 and 13 - 26. Given that my existing cassette is 13 - 26 then I could go for a direct replacement or would one of the others be a better option [I don't need any more 'help' to get up hills but perhaps could do with 'help' to go faster downhills]

    Thanks

    If no more help is needed for the uphills then I'd take the 12-25. pretty much the same uphill gears but you gain another cog at the other end so wo't spin out just as quickly as you would on your current cassette.
  • richard36
    richard36 Posts: 346
    The triple is 52-42-30
  • lesfirth
    lesfirth Posts: 1,382
    you will need an old long cage mtb mech to make an 11-34T work.

    anything less than 1:1 on a road bike is pointless. you would be better of walking as you will be travelling so sloly you fall off anyway or the front wheel rises up and you land on your back.

    I have used a combination of 28T chainring with a 30T sprocket and I can assure you that I never came close to that prediction, sitting on my saddle or out of it. In that gearing at a cadence of 70 rpm your speed is over 5mph. That is running speed to me not walking and it is much easier pedaling than walking.I need that sort of gearing on 20% gradients. In my youth I didn't but that was over 50 years ago.