Getting a cartridge BB out??

Well mine looks like this:

If you can get hold of Plus Gaz then so much the better but a strong penetrating lube or spray should be used here. Take the seatpin out (or bottle bosses) and spray copious quantities of this into the BB shell. If you have a hole under the BB for the cable guide then spray copiusly in there too. Leave this for a good 24 hours to soak in and hopefully that should help loosen off the corrosion. The next part doesn\'t sound nice but it works wonders! Grab a reasonably weighted hammer (mine is 16oz) and give the axle a good hit several times from each side; this has the effect of \'cracking\' the corrosion and freeing things up considerably. The next stage is to grab a long breaker bar and socket fitting BB tool. A 2ft breaker bar should help here. If you can get someone to hold the frame solid whilst you are pushing down and rotating the breaker bar with very hard jerks rather than steady applied pressure. Try snapping it back and forth in opposite directions to further loosen the corrosion bonds.

OK, I now have a bit of another problem I think :-( Just had a look at the frame to see what could be done and it seems the bike shop also wrecked/stripped the drive side of any teeth... god d*amnit!

Here's how both sides look...

Plastic thingie:


The other side (so the actual cartridge where they tried yesterday in the bike-shop):


Is there anything that can be done to get these things out when the teeth are gone?? Surely Shimano must have thought about some "back-door removal procedure"?? Or is there only the "Heat it up and dry banging it out with a big hammer" option left? Damn this really aggrivates me!

If all else fails and you really want to do up the frame. You could have a frame builder remove and replace the whole bb frame section. My husband had that done to his tourer, not for the same reason. It's not cheap though. :cry:

Alison

you could try removing a section of the flange where the "japan/shimano" wording is , and then try knocking it around in the direction it should be unscrewed (hammer/chisel) ????

Heat and hammer looks like the only option now. Use a sharp cold chisel and try to get it hooked on the remains of the teeth or get a sharp punch and make a good indent before you try to tap round. You need to hold the frame still, in a well padded vice or on a sandbag.

And you still have the option to weld a small lug onto the cup as a last resort.

It will come out, it just may take some bloody mindedness.

Stand on the frame and use a cold chisel and a lump hammer and work the cup round.

Carefully! :shock:

Two options which i have done in the past.

1: Get local welder to weld a metal bar to the drive side cup and axle. use as the wrench. Done this a few times while I was managing a shop

2: 5 tonne press! from the drive side the plastic cup will have no chance of stoppin the axle poppin out!! Then you will have to cut the remaining drive housing into 3 and then knock out he pieces. and same for t'other side :twisted:

I would just J-B Weld a cup removal tool to the BB, wait till it dries, then turn it out.

There is no such thing as 'never' when it comes to bike maintenance. Your LBS should know better

At this point I would hold the frame over a vice horizontally and grip the outer flange of the BB in the vice very tightly and then turn the frame round slowly....