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Compact to bigger chainset - Shimano (lazy thread)

  • 06-03-2011 08:54PM
    #1
    Closed Accounts Posts: 112 ✭✭


    This is the type of question which annoys myself - 'why doesn't the guy just google it?' But maybe I can get a quick answer here and also a possible deal .
    I'm thinking of changing my Ultegra compact chainset (110 bcd) for a 130 bcd chainset.
    The question is, what's the smallest inner chainring I can get on the 130, and where are the good on-line deals.
    Secondly, anyone want to swap a 170 crank 130 bcd for my compact - it's ultegra in good condition? It's one of the more modern ones with the hollow spindle.


Comments

  • Registered Users, Registered Users 2 Posts: 415 ✭✭100Suns


    Are you changing cranks to fit bigger rings? You can get bigger rings to fit on a 110 bcd. You don't need to change the cranks to go to a 53 for instance. I'll dig out the name of the French manufacturer's website if you want to check out different sized rings for 110 bcd.


  • Closed Accounts Posts: 112 ✭✭Pat Kavanagh


    Hey, I never thought of that. It makes sense and would be easy to reverse - thanks, and looking forward to info if you can get it.


  • Registered Users, Registered Users 2 Posts: 68,173 ✭✭✭✭seamus


    Just note Pat that many double/compact front mechs have a 16T limit, so if you go for 53T on the big ring, you'll have to upsize to a minimum 37T on the inner ring.

    Some Shimano front mechs can handle 20T, but they're rare enough.


  • Closed Accounts Posts: 112 ✭✭Pat Kavanagh


    Thanks Seamus.
    37 sounds good for innter but I wouldn't envisage going to 53 on the big one. I can't imagine myself ever needing a 53/12!
    What would you suggest for Cat 4 racing - middle of the bunch rider.


  • Registered Users, Registered Users 2 Posts: 415 ✭✭100Suns


    http://www.specialites-ta.com/gb/plateau-syrius.html

    The 52 should work with the 37 on a shim dérailleur.


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  • Registered Users, Registered Users 2 Posts: 15,995 ✭✭✭✭blorg


    You can race A4 on a compact 50/34 no problem, although 53/39 is better. What a standard gives you is better front shifting. If you switch dont go smaller than 39 on the small ring, or I guess 38 if you go for a 52 big ring. The closer ratio is a bigger deal than 50 vs 52/53. On the other hand, in many races on a 50 you would never need to front shift anyway, you can stay in it longer.


  • Closed Accounts Posts: 6,679 ✭✭✭bcmf


    BBB do 110 bcd rings up to 53.


  • Registered Users, Registered Users 2 Posts: 370 ✭✭DonalK1981


    I would be interested in your chainset/crank. Just for aesthetics mind, have ultegra all over but brakes and chainset, so looking to get it sorted. Not strong enough in the leg dept yet for the double...


  • Closed Accounts Posts: 112 ✭✭Pat Kavanagh


    I put in a 38 small ring and that did the job just fine.


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