Changing gear ratio

Mac9
Mac9 Posts: 134
edited October 2013 in Workshop
Hi all!

I've just bought a second hand Ribble on eBay that is a perfect fit for me frame and crank wise. It is six years old but is in decent condition.

The groupset is a Shimano 105 which is what I was looking for so it's all good so far.

However, the gearing is 52/38 x 23/12 which is nowhere near small enough for a wimp like me in the hills!

I'm no expert on this sort of thing though. My old bike's smallest gear was 36x25 which was just about ok. Will I have to change both the cassette and the front chain rings to help my situation or can I just pop a 28 tooth 9 speed cassette on the back?

Any advice would be greatly appreciated!

Comments

  • Mac9
    Mac9 Posts: 134
    Sorry I amost forgot!!

    A more pressing issue is that when I try to change gear on the front with the little lever (the one behind the main brake lever, sorry but I don't know its proper name! ), the big lever moves too as it catches. I therefore have to try to hold the big lever still with one finger to change.

    Is this a common problem that can be rectified with a change of cables or something similarly straight forward? Or will I need to buy an expensive new lever?

    Sorry for not explaining this too well!
  • turnerjohn
    turnerjohn Posts: 1,069
    a 12-28 cassette will make a big difference in your gearing. you probably have a "standard double" chainset and thus a 38tooth chainring is the smallest that will fit. You could get a 50 tooth outer ring if you wanted tho.

    your shifters probably just need some tlc - try some GT85 in the levers. new cables would probably make a difference but the smaller shifter lever movement isn't effected by the cable so should move freely
  • Mac9
    Mac9 Posts: 134
    Thanks for your help, I'm delighted that just changing the cassette will be enough. I some I'll have to replace the chain too?

    Will any Shimano 9 speed cassette do or will I have to buy a 105 cassette?
  • Any Shimano or SRAM 9 speed cassette will work. You will probably need to lengthen the chain.
  • meagain
    meagain Posts: 2,331
    "My old bike's smallest gear was 36x25 which was just about ok"

    And a 38x28 will give you just a little lower!
    d.j.
    "Cancel my subscription to the resurrection."
  • Mac9
    Mac9 Posts: 134
    Just a little update on my lever and gearing problems....

    I've bought a new 11-30 cassette and a dura ace chain. As I don't know how to change a cassette, I'll pop it into my LBS to get it fitted along with my new sti lever....

    Having tried loosening the sticky lever with gt85 without success, I took it to my LBS for their opinion. I was advised that I needed a new sti lever. They offered me a sora sti for £140, but I found a 9 speed tiagra sti lever for £40 on eBay which I've bought.

    As long as the labour charge isn't too much I'll get it in on Monday.