Bike Forums - View Single Post - Ceramic Bottom Bracket Confusions

10-05-11, 08:34 AM

#3

theshoemaker

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Quote:

Originally Posted by HillRider

68 and 73 mm wide bottom brackets are English threaded, for road (68) or some MTB (73) frames. The threads are 1.37" x 24 tpi and the drive side cup is left-hand threaded. The English bb from SRAM will have the 2 -2.5 mm spacers used if they are installed in a 68 mm shell.

Italian bb shells are 70 mm wide and the threading is completely different with 36mm x2 4tpi, right hand threads for both cups and no spacers should be needed.

If the cups thread into your bb shell correctly, you have the right one.

So yes, they do thread in. The concern is with the plastic pipe with the O-rings that I believe should extend across and fit into both cups. when both sides are screwed in it doesn't make it all the way across. Isn't that a problem?

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