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Compact groupset?

sprintkidsprintkid Posts: 315
edited June 2012 in Workshop
Hello folks. Can someone tell if a compact groupset is just a case of smaller chainrings?
sprintkid

Posts

  • dennisndennisn Posts: 10,496
    sprintkid wrote:
    Hello folks. Can someone tell if a compact groupset is just a case of smaller chainrings?

    Yes, it does have smaller chainrings. Usually 50-34 as oppossed to 53-39 on a, so called, standard crankset.
  • The cranks will be different as they have different BCD.
  • davem399davem399 Posts: 269
    Apart from the smaller chainrings, the BCD (bolt circle diameter) is smaller. Standard chainsets are usually 130 and 135mm, but compacts are 110mm (I think). This precludes fitting compact chainrings onto a standard chainset to get the benfit of lower gearing in this way. I understand that the smallest inner chainring you can fit on a standard set has 38 teeth, but compact inners are often 34 teeth.
  • sprintkidsprintkid Posts: 315
    Thanks for the info guys
    sprintkid
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