Our little hobby can sometimes unearth the most knackard old shite - years of practice, grazed knuckles and swears words have given me the following:

Tools required:

quality Shimano BB tool from Park, etc

Socket set - in my case its a 24mm socket

long crank bolt - these arent widely available so you make your own by forcing a bolt into the bb axle. The BB axle is a far harder grade steel than the bolt so will make its own thread.

metre long pole or bar of some sort - in my case my towbar mounted bike rack.

1. bolt BB tool to the right side of the axle, bolt it fairly tight to prevent any damage to the tool or BB.

2. rotate socket wrench and long pole to the RIGHT, in the same direction as pedaling whilst standing on the rear stays or with another person to assist in keep the frame steady.

Always undo the cartridge side first, never the plastic bit as this will immediately disintegrate.

This method has so far been 100% successful with manky old frames. No heat required! No grazed knuckles!

Some BBs have different threads so the method above works but some investigation will be required first.

Good work LGF, i'll be pointing all BB questions here in the future

Good tip

That's basically what I've done in the past. Although I tend you use a spanner or breaker bar rather than socket as you can put too much load on the ratchet with such a long bar

quality tools sir, quality tools.

aha i can better that pic , ill put it up later!

Prevention is better than cure - I always assemble bottom brackets, seat posts etc., in fact everything, with a good dollop of grease on the threads so that things won't seaze into the frames or to each other. Even better, use some copper grease, copaslip, copper-ease.

Of course, that won't help with that newly acquired 20 year old bicycle that was originally assembled by a monkey and has been languishing, un-loved, in a damp shed for the last 15 years and has almost completely fused into a rusty whole.

Looks like you are using that piece of wall for more then just sitting on

good work shifting that!

tell me about it! ive got some 30" stilsons that no bb has beaten yet. the things you have to do sometimes just to keep the project going those steel shells hold on to a bb big-style.i shifted one recently,like you, had to harness 'other' apparatus to achieve the goal. when it gave me the initial movement it sounded like a tombstone being removed after thousands of years.

I've got a seized Shimano BB on my Bear Valley SE, I've done exactly that and the bloody thing still won't move, even a subtle application of heat and plenty of penetrating spray hasn't helped. Anymore suggestions?

you sure you are doing it right?

I even tried it out on some really knackard frames without failure

My LBS puts an impact wrench on the same park tool as above... he does a lot of business fixing craigslist "finds" for people... he knows!

FWIW, I think it might be safer than a long lever on a breaker bar which might bend your frame.

I think I know a man with one of those!

Ooooh... I'd still prefer to use a quality tbar and not a quality ratchet... Good tip though!

Mind you that looks like a Snapon wrench? Do they still replace broken tools for free?

Yes, the frame well and truly flexed as I tried to on numerous occasions hence the application of heat etc.

I'm just offering advice based on my own experience in dismantling bikes using non expensive methods for the average cycle mechanic.

Anything else is just muddying the waters.

My ratchet hasnt broken, in the ten years since I bought them

The bar was handy

Spanners can round the the tool or themselves.