Shimano "9spd" BB compatibility

[artemidorus]

I'm hoping to replace my ailing 105 BB (-5500) with a DA BB-7700, which is listed as being interchangeable with the 5500 on the Shimano front drive compatibility chart. I've heard from a bike shop that the splines on the DA BB are "a little" different from the 105 and Ultegra BBs, whereas I had thought that they were all Octalink V1. Can anyone give me the real answer?

 

[alfeng]

I'm hoping to replace my ailing 105 BB (-5500) with a DA BB-7700, which is listed as being interchangeable with the 5500 on the Shimano front drive compatibility chart. I've heard from a bike shop that the splines on the DA BB are "a little" different from the 105 and Ultegra BBs, whereas I had thought that they were all Octalink V1. Can anyone give me the real answer?

ALL of the Octalink ROAD BB splines are the SAME ...

The XTR Octalink is also the same as the ROAD Octalink, too (I currently have a DA crank mounted on a 112.5 XTR BB ... I've had a DA 7700 double & Ultegra 6503 triple mounted on it) ... and, I also have an XTR 952 crank mounted on a DA BB on one road bike ...

The XT (and, presumably LX) spline's diameter is slightly smaller than the XTR/DA/Ultegra/105 spline ... the length of the spline is different, too; but, it's sort of moot.