Chainring upgrade advice rquired

matt1631
matt1631 Posts: 13
edited March 2011 in Workshop
Hi,

I bought a Carrera TDF road bike last year as my introduction to road cycling after years of competative MTB Racing (which I will never give up although am really getting into the road scene).

The TDF has a Shimano Tiagra 8 speed rear cassette and a 50T and 39T double ring on the front.

I am wanting to add a third chainring to the front, can anyone suggest the best way to do this, is it purely a case of buying a 30t ring and adding in or do i need to do do more than that or replace either the chainring set or the cassette.

Also is this the best way to do it, my issue is I need more flexibility for tough climbs where i live in the peak district and am doing London to Paris latyer in the year that has some tough climbs.

Any advice welcome please

Matt

Comments

  • You will need a new chainset.

    Look into a compact to make life easier without the need for 3 rings. Your bike shop should point you in the right direction
    Racing is life - everything else is just waiting
  • matt1631
    matt1631 Posts: 13
    Excuse my ignorance but what do you mean by a compact, is that not the szme as just adding a third ring on the front
  • Compact chainset is 110 mm BCD whereas your standard road is 130 mm. This allows fitting of a 34 or 36 tooth inner ring. This gearing with a 25 or 26 tooth cassette is low enough for any hill

    To fit a third chainring you will need to put on a new front mech and a new rear mech as well

    Talk it over with your bike shop and they will show you thge difference.
    Racing is life - everything else is just waiting
  • Butterd2
    Butterd2 Posts: 937
    Compact chainset is 110 mm BCD whereas your standard road is 130 mm. This allows fitting of a 34 or 36 tooth inner ring. This gearing with a 25 or 26 tooth cassette is low enough for any hill (*In my opinion)

    To fit a third chainring you will need to put on a new front mech and a new rear mech as well

    Talk it over with your bike shop and they will show you thge difference.

    FTFY
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  • rake
    rake Posts: 3,204
    you want a compact 50/34 chainset.a sora or tiagra will fit the bill. and a hollowtec bottom bracket to go with it. you wont need anything else. if you go for a tripple you may need new shifters with three positions. it will most likely say 9 speed but it makes no difference with 8 so dont let anyone say otherwise.
    http://www.parker-international.co.uk/5 ... inset.html
  • maddog 2
    maddog 2 Posts: 8,114
    +1

    Compact c/set with correct BB, drop the front mech a bit, maybe a few less links in chain. Bingo, lower gears.

    Triples are horrible in so many ways.
    Facts are meaningless, you can use facts to prove anything that's remotely true! - Homer
  • keef66
    keef66 Posts: 13,123
    "Triples are horrible in so many ways"

    the chainrings are a b@stard to clean if that's what you mean. Mechanically I've never had a problem with mine and I love having both a close ratio cassette and the ability to spin up virtually any hill.