Bottom bracket help /advice please....

andyh01
andyh01 Posts: 599
edited October 2013 in Workshop
Hi, I think my bottom bracket is on it's way out, I have a trek 2.1 2012/13 model, had it for nearly a year and done 10 miles a day on it, in all weather. I'm looking to replace it with an Ultegra BB as same price as a 105 BB, however, I just remembered the trek 2.1 isn't a full 105 as I was led to believe, the chainset is an R565, will the Ultegra BB fit the bike/chainset? In the photos it looks similar threads as to what I can see on my crank, but I haven't taken it out of my bike yet. Eventually as parts wear out, I will gradually upgrade the chainset to 105/ultegra . Also if it does fit, do I need an Italian or UK thread?
If the Ultegra doesn't fit what is my best option, get it faced so it does fit or alternative BB? ideally don't want spend more then the £20 for the BB but go up to £50 as a guide to sort the BB I already have the right tool to remove/fit BB
Thanks for the help Andy

Comments

  • turnerjohn
    turnerjohn Posts: 1,069
    as long as your frame isn't an integral bottom bracket (aka doesn't have threads and thus the bearings are press fit into it) then your be fine with an external shimano BB. English thread is what you need....very few Italien ones now !
  • andyh01
    andyh01 Posts: 599
    Thanks I`m even more confused now after researching on internet, saw some reference to it it being a press fit bb and other suggest its an outboard bb I guess outboard is meaning external rather than integral :?: I've looked on the cup ends and see some letters and numbers BC137.24. The hole on the crank looks circular rather then tappered /square, I've a few photos of bike but not sure how to add them into this post thanks Andy
  • andyh01
    andyh01 Posts: 599
    Right I've found ones that will fit the frame ie say suitable for frame with b.c,1.37"x24T, however as looking to upgrade to either ultegra/dura ace, to start with I'd just do the bb and replace the crank if/when needed, would the bb work with the current crank that I have, or do you have to have matching chain set and bb ie do I also need ultegra/dura ace cranks too?
  • turnerjohn
    turnerjohn Posts: 1,069
    shimano exterior BB cranks all use the same 24mm axle so any of their BB will fit.
    i doubt your notice any difference changing your cranks tho....expect a large hole in your wallet !
  • desweller
    desweller Posts: 5,175
    FWIW chainset upgrade is probably the least worthwhile in terms of performance. Unless your BB bearing has seized or is generally running very badly there's little point replacing it; likewise, unless your chainrings have worn out (and they usually last for ages) you may as well keep your money in your pocket. If those parts are OK then I would even go as far as to say you'd be better off putting the money towards a new frameset.
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  • andyh01
    andyh01 Posts: 599
    Thanks thought that you could mix and match, yeah the bb is on it's way out, I'm not looking to replace the crank just yet, as you say, will only be replaced if/when needed although the current crank is a R 565 which is similar to tiagra I think? For now its just a question of whether I go for an ultegra bb (same price as a 105 bb) or for £10 more, go for a dura ace bb which seems to be same as ultegra but 14g lighter, what you reckon?Thanks again Andy
  • desweller
    desweller Posts: 5,175
    You won't notice 14g!

    Get a Tiagra one. Make sure the frame has been faced.
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  • bernardmcdonald
    bernardmcdonald Posts: 42
    out of interest, why do you think your bottom bracket is on the way out? it doesn't have very many miles, certainly not enough to have worn it out.
  • slowbike
    slowbike Posts: 8,498
    DesWeller wrote:
    You won't notice 14g!

    Get a Tiagra one. Make sure the frame has been faced.

    Not quite sure I understand this ... it's a popular comment and I think I understand what is meant by it .. however ..

    the frame is threaded - the BB screws into this thread and is done up tightish - is the implication that without facing off, the BB will twist .. ?
  • desweller
    desweller Posts: 5,175
    The cups are aluminium, and the thread is a pretty fine pitch. You can distort the cup if the contact pressure around the mating face is not even, which leads to a poorly supported bearing and ultimately bearing failure.

    Threads are not a good way of ensuring a square assembly.
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  • jordan_217
    jordan_217 Posts: 2,580
    Remove your current BB cups and give them a clean, just use an old rag. Clean the threads and inside of the BB shell. Apply grease to both the threads in the shell and on the BB cups and I also smear a little on the face bb face. Refit and tighten up.

    I'd be surprised if it's gone with that mileage, it probably just has some dirt/crud/water ingress and needs a bit of TLC.
    “Training is like fighting with a gorilla. You don’t stop when you’re tired. You stop when the gorilla is tired.”
  • andyh01
    andyh01 Posts: 599
    Thanks for the advice. . I knew the bb was on it's way out as the feel, noise, resistance on pedals and also could feel slight play in the pedals, I did speak to the LBS where got it from via phone to see if covered under warrenty apparently not, classed as w&t. I orded a dura ace 9000 external bb when it arrived I took the old one out, the ball barings dropped out when I took the cranks off and part of the inners of the bb came off with the crankset too so definatly had gone. After a bit of issues I have now got the new one fitted and feels smooth again...
    Thanks Andy

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