XT Octalink Cranks with Dur-Ace BB ?

It would be nice if there were a table somewhere that clearly stated
what worked with what.

Or you could just use an XT bottom bracke twith an XT crankset, and a
XTR bottom bracket with an XTR crankset, and a LX bottom bracket with
an LX crankset, and an Ultegra bottom bracket with an Ultegra
crankset, and a Dura Ace bottom bracket with a Dura Ace crankset, and
a 105 bottom bracket with a 105 crankset. No worries about
compatibility or table needed.

John Rees wrote:

| It would be nice if there were a table somewhere that clearly stated
| what worked with what. Kind of like this.

I wrote:

| http://sheldonbrown.com/bbsize

You're almost there, oh guru of guru's :-)

But where does the BB-ES51 fit in your table?

I've just updated that file with info on newer models.

I think the part that confuses folks is when they say something like
this:
"Compatible with 2003 Shimano LX Cranks only."

I never said that.

OK, so that means the BB-ES51 is a V2 spline. I would like to assume
that I can take the crankset to the local shop and end up
safe, but my ruined Coda crankset was from a V1 BB I got at an
embarrassed local bike shop.

It would be helpful to explain that, to the un-aided eye, that the V1
and V2 look a LOT alike.

Done.

I personally would like to know the difference in spline depth so I can
measure the splines and know what I have in my hand.
Shimano's tech site, of course, doesn't say.

Done.

Please, if you're replying to a posting of mine, don't send both a
posting and an email, this doubles the amount of work I have to do to
answer you.

Sheldon "Aims To Please" Brown
+----------------------------------------+
| I never did a day's work in my life; |
| it was all fun. --Thomas Edison |
+----------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

"Sheldon Brown" wrote in message
...

Lot's of 'Done's' snipped out. Man that was fast Thanks!

| Please, if you're replying to a posting of mine, don't send both a
| posting and an email, this doubles the amount of work I have to do to
| answer you.

I didn't, really.
I originally sent the post to you instead of the newsgroup.
Realising afterwards I had errered, I sent the post to where I had
orginally intended, r.b.t.
Sorry about that, capt'n'

| Sheldon "Aims To Please" Brown

John "pressed the wrong stinkin button" Rees

Russell Seaton wrote:
It would be nice if there were a table somewhere that clearly stated
what worked with what.

Or you could just use an XT bottom bracke twith an XT crankset, and a
XTR bottom bracket with an XTR crankset, and a LX bottom bracket with
an LX crankset, and an Ultegra bottom bracket with an Ultegra
crankset, and a Dura Ace bottom bracket with a Dura Ace crankset, and
a 105 bottom bracket with a 105 crankset. No worries about
compatibility or table needed.

Heretic.

Bill "where's the challenge in THAT?" S.

junk- I'm sure you'd agree it was shameful what Shimano did here with their
spline design.
God knows how many cranks have been chewed up (I raise my hand, I have
BRBR

The 'road' design of Octalink proved thru consumer product testing that it was
a poor design for MTB cranks, hence the design for XT/LX. Interesting that
theXTR, XT and LX BBs, using different Octalink designs, were unique to these
cranks. So ya can't use a XT for an LX, DA for XTR, etc. Another 'standard'
that shimano made and then abandoned(remember SPD-R?)

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"

"S o r n i" wrote in message ...
Russell Seaton wrote:
It would be nice if there were a table somewhere that clearly stated
what worked with what.

Or you could just use an XT bottom bracke twith an XT crankset, and a
XTR bottom bracket with an XTR crankset, and a LX bottom bracket with
an LX crankset, and an Ultegra bottom bracket with an Ultegra
crankset, and a Dura Ace bottom bracket with a Dura Ace crankset, and
a 105 bottom bracket with a 105 crankset. No worries about
compatibility or table needed.

Heretic.

Bill "where's the challenge in THAT?" S.

I know. Its just too simple and straight forward. But I have
recently learned mixing up bottom brackets and cranksets makes things
a bit trickier. I decided to replace the bottom bracket on my touring
bike and use a shorter bottom bracket spindle. Figuring out which
length to use and getting the front derailleur to shift inwards enough
took a fair amount of time and tinkering. And I doubt I'll actually
notice any "improvement". And I doubt if the original question asker
will notice any difference in bottom brackets either.

Freddie Fandango writes:

I'm building a lightweight bike and want to use a DuraAce BB
(68x109.5) with my XT Octalink Cranks, I also have an LX Octalink BB
with a 113mm axle, but this is heavier.

The cranks and DuraAce BB seem to fit together OK but the splines on
the DuraAce are half the length of the LX. Does this matter ? The
LX one also has a 113mm axle but the DuraAce has a 109.5mm one. Does
this matter for fitting 3 chainrings ? I currently have a tapered BB
on the bike and this has an axle length of 110mm so 109.5 might be
OK ?

There are two kinds of Octalink crank/spindle types, the one with
longer splines having been designed in response to the loosening and
failure problem that isn't caused so much by the design of the splines
but by riders who stand on pedals, right foot forward (aka goofy
footed). Since this is not as uncommon as Shimano may have thought,
Octalink cranks failed more often than the market would bear, at least
in Shimano's perception and that is why they scrapped the system.

A spline that does not have a press fit on the spline faces has
elastic backlash and, like a loose crank, destroys itself... and
loosens the retaining screw. Bearing preload and press fits, or
tensioned spokes is misinterpreted by many engineers. As is evident
from the new crank attachment, Shimano has gone to the other extreme.

The same is true for automotive overhead cams that, in earlier times,
were driven by gears which rattled with elastic backlash and besides
making hellish noise caused valve float and cam face washboard. That
also took a long time to discover. Porsche RS gear-driveshaft cam
drives were doubly bad with torsion bar like shafts AND gears. Their
last version had flywheels on the ends of the camshafts that only
exacerbated the problem. These lessons are hard to learn although
analytically they should be obvious.

Jobst Brandt

Wrote:
Freddie Fandango writes:

I'm building a lightweight bike and want to use a DuraAce BB
(68x109.5) with my XT Octalink Cranks, I also have an LX Octalink BB
with a 113mm axle, but this is heavier.

The cranks and DuraAce BB seem to fit together OK but the splines on
the DuraAce are half the length of the LX. Does this matter ? The
LX one also has a 113mm axle but the DuraAce has a 109.5mm one. Does
this matter for fitting 3 chainrings ? I currently have a tapered BB
on the bike and this has an axle length of 110mm so 109.5 might be
OK ?

There are two kinds of Octalink crank/spindle types, the one with
longer splines having been designed in response to the loosening and
failure problem that isn't caused so much by the design of the splines
but by riders who stand on pedals, right foot forward (aka goofy
footed). Since this is not as uncommon as Shimano may have thought,
Octalink cranks failed more often than the market would bear, at least
in Shimano's perception and that is why they scrapped the system.



Jobst Brandt

The splines on the xt/lx,deore are also wider, so the misfit is eve
worse when when he sticks the DA crank on that BB

--
boudreaux