2018 Marin Muirwoods commuter which gets ridden pretty much every day. Steel frame and a great low maintenance bike. However square taper BB is in process of self destructing so emptied my garage to find my crank extractor and get the cranks off but when I came to remove the BB it appears to be seized!!

Have locked the tool in place with a washer and a crank bolt but I only have a headset spanner that fits and I just can’t get the BB to budge, even the plastic(?) non-drive side! And yes, I am making sure I’m turning it the right way!

So does coke down the seat tube really work? I’ve poured maybe 1/3rd of a can down the seat-tube and was going to leave it for a while before trying again. Or do I really need to find someone with a vice?

Thanks, Alex

If it was Coke Zero, I wouldn’t expect much change.

Full fat Coke and it will work, but it needs to be left overnight…

I have used Plus Gas and or paraffin method of soaking,the spanner held in place with washers and the crank bolt,big F-off bar on the spanner.You may have to destroy the plastic non drive side though.

Thanks all, it was full fat coke from my hangover stash! Will leave it and go back to it tomorrow. Tool is locked in place with a crank bolt & washer, but think my issue is use of a 32mm headset spanner as it’s the only thing I have that fits the BB tool!

You could try hitting the end of the spanner with a hammer, sometimes the shock works. But long levers are usually the answer.

Try Plus Gas (or generic penetrating oil) then plenty of leverage and some sharp knocks (as Simon suggests).

Have tried hitting the spanner with a rubber mallet but might upgrade to a proper hammer!

Can you get a longer pipe over the spanner and then hit/lean on that?

Put tool in a vice and turn frame

Put tool in a vice and turn frame

Solid idea, but just be warned I almost tore my vice off the workbench doing something like that once.

😀

My friend got his seatpost unstuck with lemon juice, he swears by it.

Lemon juice = citric acid, similar chemical process as in Coke (phosphoric acid) – works for rust/iron oxide but pretty useless for aluminium oxide, which requires a strong alkali.

With the old Shimano Hollowtech BBs which had seized, we just used to smash them out – support the BB shell over a big bench vice and simply whack the spindle, the plastic cups just collapse.

I have found that getting some one to hold bike against a fence (with handlebars over fence) and then standing on the spanner tends to work. Might be best to borrow a big adjustable hammer from a mate if you do not have one.

wrap a rag round the bb shell, boil a kettle, slowly pour the kettle over the rag. Might expand the shell by enough to make a difference. Worked for me in the past. Then try a lump hammer on the end of the wrench.

I now want an adjustable hammer 😉😊

I now want an adjustable hammer

A oil rig I worked on about 20 years ago had an 18″ shifter with a hammer head welded to the end. It was brilliant but wouldn’t get away with it these days as we’re not allowed to modify tools.

Or do I really need to find someone with a vice?

That or a much longer lever. My LBS has a custom bit of pipework to put over the end of his existing BB tool. So far there’s nothing that it hasn’t budged although I’ve had to assist in the past!

Plastic cups can sometimes be melted out with a blowtorch but that doesn’t really help the metal driveside cup – if anything you want to leave melting the plastic out until the rest of the BB has been removed.

I’m always hesitant to try chemical methods, mostly because they’re very messy and the “chemicals” that you can get hold of in hardware stores these days are so watered down as to be nearly worthless. Coke / lemon juice is the same, it’s very weak acid.

I hate the plastic locking cups. You need to attack this one first to stand a chance of getting the drive side undone. Make sure the cup tool os ocked securely in place, then get something to extend the leverage. We’ve a box section of steel that I use with a brakeer bar on the car. I’ve been known to use a garden hoe over the end of an adjustable spanner to get freewheels off (take plastic cap off one end and put over spanner handle).

I had a square taper one stuck, a mate welded a bar to it and it came out effortlessly. You need a mate with a welder for this to work though.

Coke Zero and Diet Coke are more acidic than sugary coke so that’s a better option if you want an acid. But you don’t.

I have had good results using a g-clamp to hold the tool in place against the other side of the axle – this allows a lot more welly without the tool popping out.

Here’s what happens with all these tricks for removing things. You try them all until one works. You then proclaim that this one trick worked the best for you.

That’s why there’s so many tricks for removing things!

Good luck though 👍

Get a decent spanner. Too much torque on a headset spanner and it’s going to turn into a pretzel and may take a fair chunk of skin with it. If you’re near Cheltenham you can borrow my big adjustable.

Once you can apply a decent amount of torque it should be fairly straightforward to get out if you’ve managed to lock the tool into the BB.

That or a much longer lever. My LBS has a custom bit of pipework to put over the end of his existing BB tool.

I have a length of Al pipe, from an old antenna installation at work, for this very purpose.

It’s also the exact diameter to tap on headset cups onto forks (1 1/8″ lower cups).

I snapped a headset spanner (not a cheap one either) taking an old bottom bracket old. Left a nasty sharp spike, thankfully i only stuck it into the floor mat, and not my leg.

I now have a big King Dick adjustable. That makes me snigger every time it comes out of the toolbox.

So wasn’t getting anywhere with the headset spanner so took it to the LBS who brought out a long breaker bar and got it out pretty much instantly! So I’m off to get myself a 1/2″ breaker bar (although I do like the idea of King Dick adjustable!!)

Thanks all!

I had to resort to a bit of heat from a propane torch to heat/expand the BB area of the frame. (Luckily the frame was getting powder coated for my son)

Also had the tool locked into the cup with a g clamp and the tool in a vice turned it both directions back and forth as it was being unscrewed.