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Brake calipers size

Chrisw1980Chrisw1980 Posts: 39
edited August 2009 in Road beginners
I am trying to buy a new set of brake calipers but what do the sizes mean i have seen on line and you can choose from 2 options 49mm or 57mm what are these sizes????



  • jairajjairaj Posts: 3,009
    at a guess the length of the caliper? bigger = better braking?
  • gkerr4gkerr4 Posts: 3,408
    it's the "drop" size - bikes made to take full mudguards usually need 57mm (or deep drop) brakes - most 'racy' biles use the shorter drop - campagnolo don't even make a deep drop caliper.

    You need to measure the distance from the mounting bolt-hole (in the fork or rear stay) to the middle of the braking surface on your wheel rim and buy the caliper that meets that size requirement.

    hope this helps!
  • gkerr4gkerr4 Posts: 3,408
    oh - what bike it is you are buying them for - someone will probably know what type you need on here.
  • kozzokozzo Posts: 182
    Brake pads' reach.
    Choice depends on how far from the rims calipers are installed .

    i.e. Miche 40-50 or 41-57 (often in older frames)
  • keef66keef66 Posts: 13,123
    Yep, it's the drop. My racelight tk requires the longer drop because it's designed with the extra clearance for full mudguards.

    Presumably the shorter drop, with the pads closer to the caliper mounting, results in less flex under braking so they could be considered better
  • Monty DogMonty Dog Posts: 20,614
    Short drop calipers are usually stronger - less flex - and lighter.
    Make mine an Italian, with Campagnolo on the side..
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