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View Full Version : Chinese BB cups--"-bash ins"



Ticktock
05-04-2013, 08:02 AM
Hi,
I finally got round to measuring a couple old BB cups I have lying around .
These are used as repair for damaged threads for screw ins, and as straight replacement in undamaged threads.
Well, undamaged until these are fitted--it is a one way trip, once used you must continue to use them, as the threads are crushed by the press fit . In practice they are usually bashed in with a big hammer, hence my name for them.
They work well, seem to last OK, easy to install and replace, and to adjust. All the adjustment is on the axle, so instalation must be done using a full set of parts--you can't use the axle from a screw in set.
I do not know what size the threads are in the BB that the larger cups are used in.
7056
Standard axles here can be tapered square with a nut to retain cranks, or cotter pin. I have not seen one with a bolt to retain the crank.
If you want any of these, and can't get them , let me know.
If you are wanting to make your own BB shell, these are aesy and cheaper, as there is no thread to cut, and a rough finish is good for fitting.
Steve G,
beijing