Trek 1.1 Bottom Bracket help.

gethinceri
gethinceri Posts: 1,575
edited February 2014 in Workshop
I have a 2011 Trek 1.1 and would like to change the BB but can find no indication of what type/size/brand it is. If anyone could point me in the direction of a source for this info it will be very helpful.

Comments

  • If it's stock it will be a square taper one but you'll need to take the old one out to confirm the length.

    Replace with a shimano one
  • nicklouse
    nicklouse Posts: 50,675
    Take the crank off and have a look.

    Most likely a square taper fitting.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • gethinceri
    gethinceri Posts: 1,575
    Thanks both, so likely any shimano square taper as long as the right length?
  • patrickf
    patrickf Posts: 536
    Most likely as above a 68mm BSA square taper. That's what was on my 2011 1.5.
  • I think my 2010 trek 1.5 had a 103mm long JIS BSA square taper. It's an unusual length to the suit the awkward FSA Vero chainset which I think is the same on the 1.1 you have. Basically measure the overall length of the axle.
  • Planet X have them for a Ayrton. or a token carbon bodied one for 20. I've used both and the token one "appears" to have better bearings than the rpm.
  • Hi. I have a 2012 Trek 1.1, and I've recently upgraded the square taper bb to a Hollowtech II bb. A 68mm english thread is the spec you are looking for.
  • sark716 wrote:
    Hi. I have a 2012 Trek 1.1, and I've recently upgraded the square taper bb to a Hollowtech II bb. A 68mm english thread is the spec you are looking for.

    68mm is the width of the BB shell, same as all (most) road bikes. BSA english thread. BUT the thing that varies (even between BB's with the same thread and 68mm shell) with square taper is overall length and the taper itself. This is specific to the the crankset used so that the combination will give you the correct chainline. If you are not sure which BB length to use just look up the crankset, it should tell you which BB length to use to give you the correct chainline. If you have an FSA Vero compact crankset you will (probably) need a 103mm long JIS 68mm BSA BB. Shimano don't make this size so you will have to use something like those I mentioned earlier or bite the bullet and upgrade the whole crankset and BB (unnecessary).
  • gethinceri
    gethinceri Posts: 1,575
    Thanks all.