Removing square taper Shimano BB

[Cours]

I have the correct tools and an online instructional video but for the life of me i can't free this splined Shimano bottom bracket. No amount of BFI will shift it.

Its a UN55 and looks exactly like this.

[ Use the EDIT facility - if necessary . .. the button with the pencil icon : Graham ]

[fixedfixer]

Assume you are aware that it has a lefthand thread?

[AndyK]

Assume you are aware that it has a lefthand thread?

... on the right-hand side of the bike, but a right-hand thread on the left-hand side of the bike. Always start by tackling the one on the left-hand side, as it is slightly more likely to come loose first.

If all else fails, invest in this wonderful tool, which screws onto the axle to hold the tool firmly in place while you work: https://www.bike-discount.de/en/buy/tac ... dard-26325 . Mine has successfully tackled many stuck BBs that normal extractors couldn't manage.

[fixedfixer]

I use and old crank bolt and large washer on the axle to keep the standard tool on place. A large spanner usually provides the leverage. If really stuggling, try removing the seat post and spraying some penetrating oil down the seat tube and leave overnight.

[NUKe]

You haven't mentioned the frame material, so assuming Ally or steel, Try pouring a kettle of boiling water over the BB shell, it can help to crack the corrosion.

[Cours]

Its steel. I think I'll invest in the tool pictured above. I definitely need more purchase on it, I've fit an Ice Tool and it just slips off at the first sign of any decent pressure.

[Cours]

Assume you are aware that it has a lefthand thread?

Its an. Italian frame/bb so it actually has a RH thread.

[slowster]

Its steel. I think I'll invest in the tool pictured above. I definitely need more purchase on it, I've fit an Ice Tool and it just slips off at the first sign of any decent pressure.

That version of the Tacx tool is for Octalink, not square taper. It's discontinued and no longer available from that website, but I imagine you could still find it for sale elsewhere on the internet. I think the Tacx version for square taper has a black colour coded ring, instead of the green one, but a better quality version of the tool is the one made by VAR:

https://www.amazon.co.uk/VAR-Shimano-Drive-Bottom-Bracket/dp/B004YJ2WK4

However, as per a recent thread, there is also a tool you can buy to hold your existing tool in place:

viewtopic.php?f=5&t=124566&p=1267403&hilit=tacx#p1267403

My tip in addition to the others already provided above, is to use a small light hammer on the spanner you are using on the tool, and give it repeated (relatively light) taps.

[Stradageek]

I use and old crank bolt and large washer on the axle to keep the standard tool on place. A large spanner usually provides the leverage. If really stuggling, try removing the seat post and spraying some penetrating oil down the seat tube and leave overnight.

I then have a socket that fits over the standard tool (washer/bolt holding the tool in place needs to fit inside the socket) and put my Britool strong bar onto the socket - bike wheels on the ground and heave!

A bit of heat is sometimes needed too, +1 for the kettle

[mattsccm]

Clamp the tool in the vice and turn the frame.

[AndyK]

Clamp the tool in the vice and turn the frame.

Or clamp the frame in the vice and turn THE WHOLE WORLD!!!!!!!111!!!

<ahem>

Sorry, yes, slowster is right - I didn't look too closely in my previous post and put a link to the wrong version, and it seems both are discontinued anyway. Mine is of course available for hire at very reasonable rates. The VAR one looks as if it works in the same way.

[Brucey]

I bolt the shimano tool to the BB and (like stradageek) I have a big socket that goes over the tool and the washer. The socket can be a 3/4" drive one, with a 5' long breaker bar on it if required. The immovable object meets the unstoppable force.....

cheers

[Cours]

Success! Used a rear skewer and a large washer to lock the tool in place, few taps on a spanner with the hammer and bingo. Many thanks to all.