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Replacement front derailleur

wotnoshoesehwotnoshoeseh Posts: 526
edited September 2019 in Road buying advice
I was about to install a Tiagra 4500 groupset to a frame I have here. The problem I have is that the front derailleur is a band on type with a 34.9 band. I need a 31.8.

Other than a FD4500 front derailleur, and as I will invariably be trawling the bay (or other sites) looking for a replacement, what other series are compatible with the ST4500 levers?

I'm thinking....

I've seen FD4503 available but I'm not sure if there is a fundamental physical difference between that of the triple and the double? Any advice greatly received.


  • Cheers. Good call
  • You can just get a reducer.

    Google or eBay this - Shimano SM-AD17 Front Derailleur Clamp Band Reducing Adapter - 34.9mm to 31.8mm
  • Or, you could just ask your LBS. Every Shimano FD from new now comes with the adaptor shims. They make all band-on ones these days to fit a 34.9 tube, saves manufacturing cost if they don't have to do different clamps sizes, and ship them with the little plastic semi-circular spacer shims to suit 31.8 and usually also 28.6 mm tube diameters.

    Your LBS probably has a box full of spares.
    Open O-1.0 Open One+ BMC TE29 Titus Racer X Ti Seven 622SL Kestrel RT1000 On One Scandal Cervelo RS
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