BB issue

mattsccm

Senior Retro Guru
After a couple of hundred miles on my fixed pre war Dawes I noticed that the Bb was moving to the right. It went about a cm!
I pushed it back and finished the ride. When I took it out to check I realised that the BB was threaded into a sleeve. It was that which was moving. There are absolutely no signs of any brazing etc . Am I correct in assuming that this sleeve would have been pressed in.
Am I missing something.
The BB shell looks just like a normal BB albeit with no threads and about 4mm greater in diameter.
 
You might have a Baylis Wiley unit bottom bracket. These were mainly used in bronze welded/fillet brazed frames, but also as a repair.
The RH cup has a flange similar to a standard cup, but with a taper that is supposed to help locate it. The LH cup has a locking ring with a similar taper. Generally these were also located by a longer greaser. Probably the bracket shell has stretched slightly, due to being ridden with the sleeve being slightly loose.
 
Could also be a Thompson bottom bracket - they had pressed-in cups with the thread on the axle, but I've never popped mine out to compare the size with a conventional threaded one. A good idea in principle, but in practice they work loose and the cups make creaking noises in the bottom bracket shell.
 
The original BB is out. It just came out like any other cottered BB. Currently running a no name cheapy to match the fixed wheel.
It does have a grease port but its just a very short tube in the shell by the seat tube. I wonder if something is missing which holds this tube in.
It is one tube all the way through with normal English threads on it. I can assemble the BB in it. Indeed when the pedals were taken off I pushed this BB with this shell threaded on , out by hand. The frame would be too big for a "normal" BB even if this was put in to replace knackered threads.
 
Hi, assuming it is an BW oil bath B/B, it works with by clamping type arrangement, the lock ring should have a lip on it. It could of come loose for two reasons, the locking ring is not correct, or the actual B/B shell has worn a touch and the ring was not clamping on it. I have had this happen to me and I had a friend of mine, take off some of the lip off, on a lathe. Put a photo up, if you can, just to make you aware the oiler should not really be stopping it rotate, the clamping should. Terry
 
Drawing of the Bayliss-Wiley unit. Is it like this? According to the drawing there should be shouldered cups both ends.
 

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No lockring on this bit of tube. Is that what you mean? It looked just like part of the frame. It didn't know it was there until it moved. I can't say if it was painted as there isn't much of that on the frame!
Is that inner sleeve part of the BW BB?
Maybe its moved as I am using a modern BB which of course has no left lockring, just a plastic cup that does not protruded past the shell.
 
As you can see from the drawing, it is held in by a locking ring on the adjustable cup, which you do not have, so there is nothing to stop it moving across.
 
And there is the bugger.
Haven't got a square taper Bb with a big lockring.
Suspect it may get a smudging of mig weld.
 

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