Getting a cartridge BB out??

[Void(EN12-82)]

Hi it's me again

Uhm... well, I had just started stripping my S-bike frame. Took the rear end off, took all the parts off, found out that the Rock Shox MAG-21 was even still 1 1/4" (yay! my first)

And now comes the hard part... the BB. It has to come out for me to have the front part powdercoated in red. Problem is, it's a cartridge BB from shimano. Dunno if it's a UN72 or something, but it's square tapered, and you have to put in the non-drive side first and after that the cartridge with BB and bearings (they are one piece).

PROBLEM: The "cup" from the non-drive side is a plastic one and there ain't no "teath" (you know, where the tool grips in to get it out or in) left. Probably some *^&%#)^! has tried getting it out and broke off the teath.

Took the frame to 2 bike shops to ask for help... first guy didn't even know what frame it was (he thought it was some bike from Halfords and it would not even be worth getting the BB out in the first place). He tried reluctandly and after messing around with the BB tool on the none drive side his conclusion was "Yep mate, you're right... there ain't no teath left". Second bike shop also kinda told me I would never get that BB out.

I have heard from someone "in the olden dayz" who once told me you could also tap out those cartridge BBs from Shimano. Because they are actually like loose bearings in a metal casing that screws into the BB shell... anyone have any thoughts about this? Or could I just take it out from the drive side (they tried that but their tool snapped out).

I really need to get that BB out. Would hate to see my lovely S-bike go away just because some idiot wasn't careful on a piece of plastic :-(

Any help is appreciated here... thanx all,

Void

 

[stevek]

Forgive me if I've got this wrong but can't you just remove the b/b from the other side and then get the plastic cup out? (Stanley blade or suchlike). It is a bog standard square taper unit yeah?

That's how I've just changed my square taper b/b; left the plastic cup in the non-drive side and undid the cup on the drive side and withdrew the b/b.

 

[stevek]

Oh, not wishing to teach you how to suck eggs but don't forget the drive side is a left hand thread (clockwise to undo).

 

[Graeme]

Hi it's me again

PROBLEM: The "cup" from the non-drive side is a plastic one and there ain't no "teath" (you know, where the tool grips in to get it out or in) left. Probably some *^&%#)^! has tried getting it out and broke off the teath.

You need to take out the drive side, metal cup, first, just make sure you apply as much pressure inwards as you apply to turning. It can also help to tap the tool round sharply as long as you make sure it is pressed in firmly. Remember the drive side is clockwise to loosen.

Once the drive side is out then you can try to tap the left hand cup out with a pin punch or a small old (not sharp) chisel. If it wont tap then cut it out. Run a Stanley knife blade across it's length in a few places then break it out. You may score the thread in the frame slightly but if you are careful it will be barely a mark, all you are doing is weakening the cup so it breaks out easily. You don't need to cut right through the cup.

You could also try pouring boiling water over the frame before you try tapping it round, it will soften any locking compound that may have been used.

 

[Void(EN12-82)]

Well, the weird thing is that at the bike shop they tried getting the drive side out and it wouldn't even move... I also have one of them wrenches myself, but didn't dare to touch it because if the drive-side is stripped as well there is no "using the wrench" anymore.

Uhm, yeah the BB is just a standard cartridge shimano thingie... I think not an expensive one, because I have seen them with a metal non-drive side as well.

Anywayz, I'll have a go with my wrench then. Mine also has a bolt you can put through the wrench into the BB spindle so it won't shoot out. I read on the internet about some dude who put the frame on the ground against a wall, attached the wrench to the drive side and just stood on the wrench until it would turn towards the ground...

Think this is the way to go then? Oh my, oh my, oh my... my poor lil' S-bike :-( :-( They even painted it with hammerite, oh the horror, the shame, the indignity

Oh yeah, with "cartridge BB" I mean one of those BBs that has two cups that look like an "inverted octalink spindle"... just wanted to get that clear. So it's no cartridge BB like one of those syncross or titanium thingies (or isn't that called cartridge??)

 

[Radar]

Top tip!

Go out into the garden, lay your frame on the grass, press it down into the soil/grass. Put gartridge tool into BB cup, press firmly down onto it with the palm of your weakest hand (Really get all your weight onto the BB cup tool). Works a treat, stops the cup tool twisting out of place and wrecking the cup teeth. Last time I tried to do this in a hurry (ie not this method) I wrecked a cup on a RF Taperlock.

 

[B3]

Get yourself a blow torch, like the plumbers use, hold the tool in with a crank bolt with some washers under it so you actually tighten the tool into the bottom bracket with the crank bolt.

Now gently heat the bottom bracket, this will loosen everything and make extraction easy.

 

[orange71]

I use a shimano BB removing tool

lay the frame out on the grass and then use one of these:

except mine isn't your standard 6" or 9" - it's 24"! There's enough leverage there to get most things undone, you just need someone to stand on the BB tool on the frame while you turn the spanner. I then cut the plastic non-drive side bit out with a knife/screwdriver being careful not to damage the thread.

I've done this several times and it has always worked. good luck!

 

[Russell]

If you're really struggling, use the blowtorch, but melt the plastic cup with it. Its messy and requires a fair bit of cleaning up, but it works.

 

[rc300]

I use a shimano BB removing tool

lay the frame out on the grass and then use one of these:

except mine isn't your standard 6" or 9" - it's 24"! There's enough leverage there to get most things undone, you just need someone to stand on the BB tool on the frame while you turn the spanner. I then cut the plastic non-drive side bit out with a knife/screwdriver being careful not to damage the thread.

I've done this several times and it has always worked. good luck!

with the bb too use a large washer and the crank bolt to secure tool from jumping the spline. works in a similar way as the 'tacs' tool does.