will i need a new bottom bracket

dimmockg
dimmockg Posts: 471
edited January 2017 in Workshop
hello all

in anticipation of going from 10 speed triple ultegra (6703) to a combination of 2 x 11 speed (ultegra/105) would I need to change the bottom bracket to accommodate the difference in chainset?

Comments

  • imposter2.0
    imposter2.0 Posts: 12,028
    No. Although if you have a spacer fitted, it might need to come out.
  • dimmockg
    dimmockg Posts: 471
    ok thanks, I had a feeling it should be ok due to both being HT2

    Can check the spacer situation, the only "issue" I have is the BB in the frame is press fit, so I guess this would be a trip to LBS to un-press it and press the new one

    Carbon frame so want it done properly
  • keef66
    keef66 Posts: 13,123
    Still OK with a press fit BB. Any spacers will be on the crank spindle so they'll come off when you take the old one off.

    I have a CR1-SL with a factory installed Shimano press fit BB. I've swapped chainsets several times; it's had a 105 5600 triple, a Tiagra 4600 standard double, and a CX double, depending on what rides I'm planning and whether or not my knees work.

    The double chainsets need no spacers, the 105 triple has one each side, but the D/S one hides behind the spider so it's easy to miss.
  • svetty
    svetty Posts: 1,904
    If the old BB has a good few miles on it this would be a good opportunity to replace it whilst you have the cranks off no?
    FFS! Harden up and grow a pair :D
  • keef66
    keef66 Posts: 13,123
    You can change the BB at the same time, but if it's still smooth I'd probably leave it. When it does need replacing it's simple enough to tap the old one out and press the new one in. I bought a diy headset press off eBay for a fiver; used it to press in the headset cups on mine but you could easily use it for a BB

Categories