lower gearing

brinorl
brinorl Posts: 10
edited January 2013 in Workshop
I want to lower the gearing on a bike with a 50/34 chainset on, 110mm bcd, and my largest rear is a 30. I have changed the 50 for a 46, and this is fine, but there is no way to go smaller than the 34, because of the bcd, but this is where need the smaller ring. Its a Truvativ GXP bottom bracket. Will a MTB chainset work, or will the Ultegra double lever operate a triple chainset at a pinch, giving me the 30 tooth option?

Comments

  • Mad_Malx
    Mad_Malx Posts: 5,005
    If you use a triple chainset with a double shifter you will be restricted to two chainrings. These will probably work ok once you have set the stop screws, but the gearing will be really tiny with most MTB chainrings.

    You can get lower gears by swapping the rear cassette to an MTB - eg 12-34, but will almost certainly need to change the rear derailleur and check your chain length.