RetroBIKE general guide to stubborn bottom bracket removal

[cce]

I always do stubborn BBs on the floor, no need to torque your work stand and break it

My volunteers are always impressed at how easily an old-school fixed cup will come out when it's clamped in a vice and the frame is turned

 

[coomber]

I always do stubborn BBs on the floor, no need to torque your work stand and break it

My volunteers are always impressed at how easily an old-school fixed cup will come out when it's clamped in a vice and the frame is turned

I had the wheels on the frame, had held of the rear of the frame and a friend did the levering (the hard bit).

 

[Neil]

Just done one today, that didn't initially seem to want to budge.

I didn't have anything that long handled, nor did I have access to a bench vice - and a black and decker workmate does not equal a bench vice, but in fairness, doesn't fall apart when you hoof the fecking thing, either.

Right foot, 4th toe: 0, Black and Decker workmate: 1. It was a late kick-off, and some dubious fouls, but the workmate withstood the punishment like Leonidas' army. Well when I say that, it didn't fall over or look the slightest bit perturbed when I booted it. In retrospect, that's just hyperbole, isn't it... a workmate has precisely nothing in common with an ancient greek army.

What I did have is some Plusgas, a decent BB tool (actually a genuine Shimano BB tool) a crank bolt with a big metal washer holding the tool to the BB cup. Tried a bit of gentle shocks using a hammer - didn't seem to do anything to the non drive side. Then I had a go at the drive side, carefully squirted a bit of Plusgas in the thread bit, whilst covering the rest with a cloth.

Then some gentle strikes with a hammer on a big hefty spanner - couldn't believe it moved so easy. Drive side then came out easily, and when I moved to the other side, the non drive side cup would turn by hand.

Threads were clean and there looked to be some grease - I can't remember whether I took it out when nearly new, to apply some grease (did build a few bikes at the time, so may have done) or whether that's simply how it was assembled, but it's been in since 95.

Lessons learnt - UN51s seem bombproof - the thing is still silky smooth. And penetrating oil and light shock hits with a small hammer may be able to break the stiction, if moderate force hasn't.

 

[26er]

.

 

[The History Man]

Blueridge is being b*astard BB drive side cup. Two of us have just had a go. soaked it overnight, tried a vice. Not tried heat yet. off to find a scaffolding pole.........

beginning to doubt: drive side = left hand thread

 

[26er]

... burn it out.

 

[dyna-ti]

You need to bolt the tool to the BB and id go for hammering over an extra long bit of pipe. The sharp hits would do more to breaking the corrosion's hold than putting strain on it itself :?

Just a thought

 

[coomber]

Re:

Sharp hits on the scaffold pole

 

[syncrosfan]

Good quality BB tool (I use the Park Tool one) + impact driver (I use a Milwaukee M18 cordless one from work). Defeats even the most stubborn BB. I will not even attempt to use muscle power to remove any BB that seems stuck. One word of warning though, it will be LOUD! (my wife almost got a heart attack when I used the impact driver at home one day). The advantage of this method: you can continuously press the tool into the BB cup while the impact driver does its job beating out the seized cup. Generally speaking the left hand cup (non -drive side) comes out easier than the drive side, but even the drive side will come out with some anti seize oil squirted in there (just a matter of time).
This method never failed me but you'll need access to a good quality impact driver (they're expensive).

 

[JoeG]

Sheldon Brown has a good way of using a bolt and washers to free a stuck fixed cup.

http://sheldonbrown.com/tooltips/bbcups.html