swapping from Shimano 2300 to Tiagra

djwc Posts: 39
edited March 2016 in Workshop
I'm thinking of buying a shimano tiagra triple (http://www.ribblecycles.co.uk/shimano-t ... -groupset/ ) for my bike as my old gears are a bit worn, and I'm struggling to get up a couple of hills near me.

I posted something similar to this a while ago and a poster said my bottom bracket may not be compatible with these new gears.

Short of buying the gears and trying to fit them, is there a way of finding out? My bike is an orbea aqua t23 that I bought in 2012.


  • Can't speak specifically about your bike, but I upgraded my 2300-equipped B'Twin Triban 3 to a mix of Tiagra & 105 with no problems at all. I seriously doubt your Orbea will have an incompatible BB shell - I expect it will be 68mm BSA (as was my Triban) and the Tiagra BB will be a straight swap.

    What ratios are you running on your Orbea? Tiagra cassettes are available up to 34 teeth, which would give you crazy-low gearing (1 : 1) with a standard 50/34 compact, and going from 8-speed to 10 should mean jumps between gears shouldn't be too bad. I'm not sure why you'd go for a triple.

    My B'Twin originally had a triple & I was glad to be shot of it - fiddly to find the right gear & a pain to set up.
  • Ste_S
    Ste_S Posts: 1,173
    You'll need a different bottom bracket (which will come with the groupset) - 2300 seems to be cartridge whilst Tiagra has external Hollowtech II cups.
    You frame will most likely be threaded BSA which should be able to take either.

    If you already have the tools to take off your old cranks and bottom bracket, you'll need an additional Hollowtech II tool. Will normally come with the tool to adjust the bearing pre-load cap on the left crank arm, as well as the tool to install the external bottom bracket cups.
    Alternatively, your LBS should be able to do it for you.