You should really measure your brake drop before you go out buying new calipers. It's possible (although unlikely when converting from 27" to 700c) that you might end up with brakes that are too long rather than too short!
@lae started
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You should really measure your brake drop before you go out buying new calipers. It's possible (although unlikely when converting from 27" to 700c) that you might end up with brakes that are too long rather than too short!