Hollowtech I(?) crank middle chainring fit problem

I'm trying to swap out my middle chainring on a 2000-era Hollowtech
Deore XT crank (4 bolt spider).

So I order a Shimano chainring but it doesn't fit. After fiddling a
bit, I realize that the middle and outer chainrings, although they're
the same BCD, they have different lengths of the chainring
"arms" (sorry, I don't know what they're called--they're the tabs that
have the bolt holes)! The middle ring's arms need to be shorter by
about 1/8" each to go onto the spider as compared to the outer ring's!
WTF?

So what kind of middle ring do I need? Can anyone give me a part
number or something so I can order the right thing?

Thanks.

nork" wrote in message
... I'm
trying to swap out my middle chainring on a 2000-era Hollowtech
Deore XT crank (4 bolt spider).

So I order a Shimano chainring but it doesn't fit. After fiddling a
bit, I realize that the middle and outer chainrings, although they're
the same BCD, they have different lengths of the chainring
"arms" (sorry, I don't know what they're called--they're the tabs that
have the bolt holes)! The middle ring's arms need to be shorter by
about 1/8" each to go onto the spider as compared to the outer ring's!
WTF?

So what kind of middle ring do I need? Can anyone give me a part
number or something so I can order the right thing?

Thanks.

"2000-era" may not be enough information. On the back of the crank arms
there should be a number that tells us what series it is, and from that, we
can figure out which chainrings. Best bet would be to bring it into a shop;
most larger shops will probably have the relevant chainring in stock. I
think the number will begin with an "FC."

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA

nork wrote:
I'm trying to swap out my middle chainring on a 2000-era Hollowtech
Deore XT crank (4 bolt spider).

So I order a Shimano chainring but it doesn't fit. After fiddling a
bit, I realize that the middle and outer chainrings, although they're
the same BCD, they have different lengths of the chainring
"arms" (sorry, I don't know what they're called--they're the tabs that
have the bolt holes)! The middle ring's arms need to be shorter by
about 1/8" each to go onto the spider as compared to the outer ring's!
WTF?

So what kind of middle ring do I need? Can anyone give me a part
number or something so I can order the right thing?

Thanks.


The new XT (2007-2008) use a slightly different mount point on the
cranks you can not fit the newer rings on the older(2006-)style of
cranks,I have both and have to have 2 sets of spare rings.