[Closed] Square taper bottom bracket stuck

Mine has a hole through the middle and always used to put a wheel QR through it to hold it in place.

(I know you are, but you're def turning it the right way?)

If you get another tool without the pin you could use a bolt to hold in place.

I had a really bad one of these. I ended up taking the frame back to the framebuilder (it was a custom frame) and he used a blowtorch to get it out. Destroyed the paint, but got the job done!

Like [url= https://www.chainreactioncycles.com/shimano-bb-tool/rp-prod689 ]this[/url]

There's a Cyclo one for £9.99 on Ebay. (Can't do link on work PC)
(or I'll post you mine if you don't wanna splash out)

G-clamp the tool into the cup?

Or maybe Clamp tool in bench vice, place bike (wheels out) sideways on top of tool, relies on weight of bike to hold tool in cup, then use frame for more leverage?

You only need to keep it engaged sufficiently to start the cup winding out of the thread.

Stupid Question, you are turning it the right way? (Drive side is clockwise to loosen (LH thread)).

Getting a bolt with the correct thread pitch would be easiest solution. 10 seconds of googling suggests it's M8 fine pitch. Got a long G clamp or framing clamp that would hold it in place loosely while you get it started?

Also, (without meaning to insult your intelligence) you are turning it the correct way?

edit - beaten to it while I was away!

Don't ask silly questions cookkeaa 😉
and tthew 😀

Mine has a hole through the middle and always used to put a wheel QR through it to hold it in place.

Aye I've done that before but this one doesn't

I know you are, but you’re def turning it the right way

Yep, got the new external BB next to this with the "tighten" indicator on it, so I know that I'm turning it the right way
[url= https://i.postimg.cc/52BZbmkD/BB-threaded-cup-with-arrow.jp g" target="_blank">https://i.postimg.cc/52BZbmkD/BB-threaded-cup-with-arrow.jp g"/> [/img][/url]

Will triple check when I go back though just to be sure

If you get another tool without the pin you could use a bolt to hold in place.

I'm looking for a toll WITH the pin. My tool has no pin, just a hole, but I can't find a bolt to fit - the thread pitch is different and I don't want to wreck the threads in the spindle

Last time I had this problem I ended up taking to my LBS who used an angle grinder on the bracket...

Tool in vice and using the bike frame as a lever as suggested by cookeaa has always worked for me!

Getting a bolt with the correct thread pitch would be easiest solution. 10 seconds of googling suggests it’s M8 fine pitch

Finding an M* bolt with fine pitch is the issue, found nowt in the garage and nowt in the local hardware store

G-clamp the tool into the cup?

WINNER - I have some G-Clamps, good call! I'll try that later.

Last time I had this problem I ended up taking to my LBS

I had admitted defeat and was gong to use the LBS but they currently have a ten day backlog. I'm really glad they're so busy but that thanksfully prompted me to ask on here...

Last time I had this problem I ended up taking to my LBS who used an angle grinder on the bracket…

If only someone had that photo of Kryton's BB/crank grinder work... #legend 😊👍

Ebay for M8 fine bolt or your local fastener shop

I always use a g-clamp as mentioned above. You can hoof it up tight on the drive side as cup / axle / bb usually come out as one (nds you have to back off the clamp as the cup comes out).

Solid front hub cup and cone axles are sometimes M8 fine so a good source of threaded rod and nuts etc.

Yep, got the new external BB next to this with the “tighten” indicator on it, so I know that I’m turning it the right way

That's exactly my method. 😁 Pedals I do frequently enough to remember, but BB's are just too irregular to be sure.

ebay for odd fasteners ad Murray suggests. Bloody hell, they ain't cheap though! 

I've got one with a hole in if you want to borrow it

Are you absolutely, 100%, definitely, unequivocally sure that you're turning it the right way?

Yep, got the new external BB next to this with the “tighten” indicator on it, so I know that I’m turning it the right way

If that new BB is an English thread and the old one and frame are Italian thread.... Italian ones are rare but google it and check!
.
I have loads of square taper crank bolts and a tool which I know is a shallow enough depth to use them to hold it on to the BB. If you are anywhere near the Tweed Valley you are welcome to pop round and use them, pm me.

I'd also put a lot of oil inside the frame and leave it (on its side) to penetrate overnight before trying again

I had one like that, turned out sitting the frame upright on the floor and standing on the tool was enough to get it moving. Couldn't budge it by hand or get the tool to stay in like you but that just worked first time.

Was about to suggest the 'italian' standard which is the same both sides, rather than the english which is opposite to the direction of the cranks (making sure it doesn't loosen as you pedal)

MrsP once caught me getting the angle grinder out to "deal with" such an issue. As it was her frame she opted to try herself, clamped the tool in place and then just spent an age tapping the spanner with a hammer (and I mean tapping, not belting seven shades of sh out of it) and whaddyaknow, the damn thing came undone. I will never ever be allowed to forget this.

I use my dewalt 1/2" impact driver. Will have it out in seconds.

For years I would use methods mentioned above to hold the splined tool in place. But impact driver just gets it done quickly without putting much strain on the frame. I use it now for all mine bb's.

Only problem is you need an impact driver or know someone who has one.

Tool in bench vice and use frame as big lever. Never failed me yet 🙂

If that new BB is an English thread and the old one and frame are Italian thread…. Italian ones are rare but google it and check!

It's a Mk2 On-One Scandal, 73mm english thread

I’d also put a lot of oil inside the frame and leave it (on its side) to penetrate overnight before trying again

It's had several soakings

I had one like that, turned out sitting the frame upright on the floor and standing on the tool was enough to get it moving. Couldn’t budge it by hand or get the tool to stay in like you but that just worked first time.

If the tool ould stay on, I'd have done that a while ago

Only problem is you need an impact driver or know someone who has one.

Good idea, but I don't have one and don't know anyone handy who does have one

However, I do have a g-clamp and I'm prepared to use it

Find a shop with one of these:

https://hollandbikeshop.com/en-gb/bicycle-tools-maintenance/bicycle-tools/bottom-bracket-bicycle-tools/cyclus-bottom-bracket-tool-shimano-octalink/

I had old Specialized that we:

- soaked in plusgas. for three days.

- heated up frame & iced bb axle.

- bolted in the new long spline tool, tight.

- used good ring spanner. With the old bike stand pole on the end of - approximately 5' lever.

- used two boys and myself to hold frame down to the ground - and sent third boy out to the end of the pole

.......where a few pushes with legs from teetering boy led to a satisfyingly slow movement of the BB.

I honestly thought I was going to break the frame - you could see the alloy rear triangle flex...

If you are anywhere near Huddersfield I can get it out for you for a small charge. No damage to frame.

Only problem is you need an impact driver or know someone who has one.

Good idea, but I don’t have one and don’t know anyone handy who does have one

A local mechanic would have a windy gun and as suggested would probably take seconds. If your tool has a 1/2 inch drive, take it all round there, armed with a couple of decent packets of biscuits and your most suggestive smile, they'd likely help.

To those of you saying have at it with an angle grinder, WTF is the technique you'd use to extract a stuck BB from a frame?? I really can't imagine how it could be effective.

Long g-clamp and some wood will do it.

Had a similar issue with locking nuts on my son's car - one was a little too tight, but the tool kept popping off, and he'd already ruined one as they were made of cheese.

Googled, solution was to park the car near the wall of the house, then just the scissor jack to press the locking tool onto the nut (with a bit of wood) - undid easy, no force needed.

A long g-clamp will hold it in place. (or get another tool that will accept a QR)

or get another tool that will accept a QR

the tool is fine, it's the spindle in the BB that won't accept a QR

The axle doesn't have a handily QR sized hole down the middle? What do the crank bolts screw into?
Sorry that's an unnecessary question. I'm bored, I do apologise

Dez..Usually blind threaded holes about 25mm deep,you had a rare thing if you could put a QR all the way through it.

The ones with through holes were the posh lightweight ones!

Sensible answer if the G clamp method doesn’t work is the soak in PlusGaz and an impact driver.

you had a rare thing if you could put a QR all the way through it.

I don't think Shimano UN72s were that rare!

Hmm,I thought all the shimano sq taper were solid, #everydaysaschoolday 🙂

I've still got 2 UN72s and 2 UN73s! #hoarder
[img] [/img]

😛

Brilliant! 🙂

My ST BB is seized in the frame of my old M2, and there I think it will remain!

It has made me review the number of ST BBs I have in my spares drawer 🙂

I had exactly this tool popping out. Tried plus gas, no joy, tried gentle heat no joy.

New Tool with flats for a spanner in the bench vise, g clamp holding it in place heat applied and frame use as leverage.

If you have a bench with a vice on it its a case of put tool in vice, add bike and turn, its surprising the amount of torque you can apply this way and ive released a lot of 'stuck' threaded BB's by doing it this way.
Option two is to clamp the tool to the BB axle,which will stop it from jumping out, add a long spanner and to that add a long length of pipe.

If you take it to someone like an engineer, its likely he'll not have a clue of these things and first attempt will chew up or rip up the splines making removal nigh on impossible. Same goes for many bike shop who dont have a real well trained and experienced mechanic working there. This is old school remember, and you need an old school bike mechanic to get it out.

Adds - You are turning it the correct way ?. Always worth triple checking.

Well, I did reply to this thread last night, but the post has vanished, there must have been a restore to solve the 502 problems that took the forum down last night. Anyway...

Here's the tool in place. You can see it has a hole to allow access, but at the moment I have no M8 fine thread bolt to lock it in place
[url= https://i.postimg.cc/256QVvx2/2021-06-22-19-04-59.jp g" target="_blank">https://i.postimg.cc/256QVvx2/2021-06-22-19-04-59.jp g"/> [/img][/url]
I've double checked and the axle / spindle is definitely solid

I dug under the workbench and it turns out I don't have G-Clamps, I have F-Clamps
[url= https://i.postimg.cc/K8Q7GQt1/2021-06-22-19-04-29.jp g" target="_blank">https://i.postimg.cc/K8Q7GQt1/2021-06-22-19-04-29.jp g"/> [/img][/url]

Guess what?

IT STILL DIDN'T MOVE. The only thing I have that I could use as an extension is a piece of copper tubing. It's not really solid enough, even though the walls are reasonably thick, it was just bending. I even tried standing on the spanner, but at that point the tol just slipped out even despite the f-clamp. I am wondering if the splines in the BB shell might be wrecked by this point 🙁

However, I've recalled that a neighbour is a power tool fan and she has said sh'll pop round with her impact driver tonight so hopefully that wlil sort it

Longer term plan is to get a proper spanner to fit this tool (i'm using an adjustable at the moment) and some kind of breaker bar/extension. Shamefully, I don't have a bench vice (at least not one that's fitted and usable, I have a lovely old vice in the corner of the garage but I've no space for it until I have a proper clean-up / reorganisation and there's no plates on the jaws)

When you first posted I thought that spanner was a bit short, iirc last one I did I had some proper long wrench on it (2 foot one). I reckon a bit more leverage and it’ll go (that and turning it the right way 😉 )

Also, could just be seized... Water gets in there. I ditched a road bike frame long ago cos the bb was properly seized. That spline system was rather crap, hence hollowtech style bbs.

Just thought of another method I've used in the past - putting the opposite cup back in and tightening to within an inch of it's life, until it moves the drive side cup. Only works if the non-drive cup hasn't got a lip (and isn't plastic).