Replacing a tight fixed cup bottom bracket

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cycleman

Well-Known Member
I’m trying to replace a fixed cup square taper bottom bracket on a mountain bike.


On the chain side I have managed to get out the 119mm axle along with the all the ball bearings.


However the fixed cup on the other side won’t budge and it looks like it’s seized completely.



I have taken it to my LBS and they could not remove it.


Would penetrating oil loosen it up enough to remove it? If so which is the best one to buy?

Is it possible to re-fit my old axle with bearings without removing the fixed cup on the other side?

The bike is not worth much (£60) , but it has a nice silver frame and I want to get it in working order rather than discarding it

Help would be appreciated.

regards

cycleman
 

HovR

Über Member
Location
Plymouth
Is it possible to re-fit my old axle with bearings without removing the fixed cup on the other side?

Yes. I've had to do this before when in the same situation as you. It is much easier with bearings in a race than loose bearings.
 

compo

Veteran
Location
Harlow
It's easy. As HovR says it is easier with caged bearings, if you like caged bearings. If you prefer to do a decent job and use loose bearings run a generous wipe of grease around the axle then set the bearings into the grease which will prevent them falling out while you feed the axle through the bottom bracket and into the cup.
 

compo

Veteran
Location
Harlow
The fixed cup can be a bother to remove. I use a big nut and bolt, the nut inside the cup and the bolt fed through the hole in the cup. As the cup is a left handed thread as you tighten the bolt it will unscrew the cup. In theory. I have a 5 foot lump of scaffold pole that I put over the half inch drive wrench and have been know to have to bounce up and down on the pole before the cup shifts.(my 18 stone helps). If it looks OK just leave it where it is!
 
OP
OP
C

cycleman

Well-Known Member
Thanks a lot for reply guys. I did not think I would be able to do it. It's gret to know. Cheers once again
 
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