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Bottom Bracket Removal
#1
Hi,

First time changing one of these things seemed to be going well.

Cranks came off fine, lockring removed and now im stumped.

I dont see anywhere where I could use to multi-tooth removal tool to get a grip onto the old bracket im not quite sure how to go at it.

Il post a couple of pics up from each side, any help would be much appreciated Smile
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#2
The left side takes a "pin spanner" tool that has two thick pins on it to fit into two of the holes on opposite sides of the axle. Note that it is hard to get much torque with these and if the BB cup is stuck at all you may need to try gripping it across the thread with large channel lock pliers, visegrips, etc. The right side take a tool that fits across the two flats on the outer edge of the cup. Here too you can substitute with a large adjustable wrench, channel locks, etc. Note that the right side has reverse threads and unscrews clockwise.
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#3
Thanks for the help,

I managed to remove the whole thing just by unscrewing the left side. The right side didnt even have threads so it just pulled right out.

I am hoping to replace the bracket with one like in the picture (only a bit longer to match the old one) is this possible?

Many thanks
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#4
(11-07-2014, 11:29 AM)Kingo Wrote:  The right side didnt even have threads so it just pulled right out.

This is a very bad sign. If the threads on the frame are badly damaged, you might be screwed. If the threads on the cup were just chewed up badly, the frame might be fine or you might be ok if you take it to a shop and have them "chase the threads" on that side of the frame.

But yes, the newer, cartridge style BBs like you show are better and available in any size you'll need. You need to know the width of the BB shell on the frame (probably 68 or 73mm) and the length of the axle of the old BB.
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#5
If the threads are damaged beyond repair you will have to acquire a BB from Velo Orange -http://store.velo-orange.com/index.php/components/bottom-brackets/grand-cru-threadless-bottom-brackets.html
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#6
Thanks for the answers, I think my explanation in the last comment mislead a few of you.

I have now realised the end cap (picture 2 of first post) screws into the frame, belonged to the damaged bottom bracket, this however looks slightly bent out of place explaining probably why it seems unwilling to budge.

I imagine without removing this end cap the new bracket wont sit right....
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#7
Yes, you have to remove this, it's called the fixed cup or the drive side cup. It does look like it is at an angle which may be bad. Note that it has reverse threads, turn it clockwise to loosen.
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#8
I managed to get the fixed cup off on the weekend with the help of a mechanic friend (car not bike..) there was no chance of the fixed cup moving, looks like it had almost been pressed into the metal of the frame with some force when it was originally put in.

We had to saw a chunk out of the fixed cup to relieve the pressure and get the whole thing off. As it stands now the threads aren't damaged as we were very careful with the saw but where the fixed cup was forced in they don't run straight anymore...meaning putting a new bracket in there could be difficult.

As far as I see I have two options, attempting to put the new bracket in with force.....buying a threadless bracket.

Thanks for the input so far!
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#9
Sounds like someone cross threaded the fixed cup. Third option is to have a bike shop run a BB tap through, but not all shops will have the proper tool.
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