[Bicyclist]

Does anyone know if the new Shimano XT Hollowtech II Arms are compatible with Dura-Ace BB's? I just noticed that my BB was shot and the Dura-Ace version is supposedly stiffer, lighter, and has better seals. (I don't know if this is the right place to post this )

 

[Brian HCM#1]

Nope, the Dura Ace is compatible with the older XTR.

 

[Bicyclist]

So you're saying these cups are compatible with old XTR Octalink splined arms? I talked to the LBS owner and he called Shimano. They said that the Dura-Ace Hollowtech BB's won't work with Hollowtech XT arms because of the different spacing (double and triple cranks).

 

[JRB]

I thought they were all the same, but don't know now. I looked and this one - http://www.universalcycles.com/shopping/product_details.php?id=1940&category=345 - is the only one that says it works with XTR and XT. I would call a shop with a good rep. I hear that all of the seal suck on those, though.

 

[syadasti]

I think the raceface external BB work with Shimano cranks. You'll have to call someone at RF to find out which ones.

 

[Brian HCM#1]

The Dura Ace may work, but only come in a 68mm or 70mm shell. They aren't available in a 73mm shell if thats what you need.

 

[Bicyclist]

Has anyone tried the Race Face BB? If it has better seals, I may be interested.

 

[JRB]

Has anyone tried the Race Face BB? If it has better seals, I may be interested.

I hear they suck. I would look at FSA if they will fit.

 

[syadasti]

I hear they suck. I would look at FSA if they will fit.

The only thing I heard that sucks about the RF system is the crankarm fixing system if you like to take you cranks on and off a lot. It would be cool if there was a comparison somewhere of all these external BBs if they work with each other...

 

[Bicyclist]

The RF BB WILL work with Shimano mountain arms. If I already have Shimano arms, then I could use those arms with the good crankarm system and the good RF BB.

 

[blue]

Waaaiit...The new external BB's come in specific sizes?

 

[Bicyclist]

I didn't think so because isn't that what the spacers are for?

 

[blue]

Silly me...the Shimanos use spacers to go between 68 and 73mm shells.

 

[Bicyclist]

Hrm... So wouldn't that mean that I could use a Dura-Ace BB?

 

[J5ive]

They all work. I've had dura ace on XT, XT on ultegra, Raceface on hone.

 

[Bicyclist]

Sweet! Some non-e-speculation.

 

[syadasti]

They all work. I've had dura ace on XT, XT on ultegra, Raceface on hone.

So what is your favorite external BB for each application (Road, XC, Trail, FR, DH, etc..)

 

[J5ive]

They are all the same from what I can tell. I've had a diablous and dura ace appart, both just use standard looking cartridge bearings. Always just grabbed the one that happened to be in the shop at the time and went best with the bike..