Shimano date codes - M900 XTR

[Once A Hero]

Having had a closer look, here’s what I found;

Seatpost SP-M900 27dia PL December 1991
Front Hub HB-M900 28H RB February 1993
Rear Hub FH-M900 32H QC March 1992
STIs ST-M900 PI September 1991
Headset HP-M900 1” PH August 1991
Bottom Bracket UN-91 107mm QH August 1992
Front Mech FD-M901 28.6 Top Pull SK November 1994
Rear Mech RD-M900 PK November 1991
Cassette CS-M900 Type Q 12-28T
Spider = Q3 ??
12t=QE May 1992
13t=QF June 1992
14t=QF June 1992
16t=QF June 1992
18t=PK November 1991
21t=QB February 1992
24t=QC March 1992
28t=QD April 1992
Chainset FC-M900 175mm 46-36-26 PG July 1991
Seatpost Quick Release SQ-M900 ??
Cantilevers BR-M900 PI September 1991
Chain - CN-7401 Dura-Ace ??
Pedals - PD-M737 ??

P = 1991
Q = 1992
R = 1993
S = 1994

A = Jan
B = Feb
C = Mar
D = Apr
E = May
F = Jun
G = Jul
H = Aug
I = Sep
J = Oct
K = Nov
L = Dec

 

[Once A Hero]

Ill take those dust covers off your shifters Pete.

Date coded for the brakes is where the straddles attach in the recess. Should be early P or Q as the chainset is the 1st generation

It’s taken me ages to get dust covers on all my M900 STIs!

 

[Once A Hero]

What is Q3 ref on the cassette spider?


No dates located on the pedals, chain or seatpost qr.

 

[Matttymm]

I think the Q3 is the model variant.

The date stamp should be on the front of the cogs Pete like the picture.

 

[Matttymm]

Pic

 

[Magpiegifts]

Seems your cassette is mismatched sprockets exactly the same as my type q cassette. Or was this how they were released?

 

[Once A Hero]

I think the Q3 is the model variant.

The date stamp should be on the front of the cogs Pete like the picture.

Yep found all of them - they vary for each cog.
Haven’t looked at the front body of the spider, just the rear where there is a Q3 code.

 

[Once A Hero]

Seems your cassette is mismatched sprockets exactly the same as my type q cassette. Or was this how they were released?

I’m gonna have to go a find and check another now! I suppose the only way to know if the cogs were mismatched would be to check a NOS boxed one, which I don’t have.

 

[trailwright]

Yep XTR first appeared in ‘92 Shimano catalogues, so it seems feasible that production commenced in ‘91.
I have a rear mech that looks to be stamped with an O as it’s first letter which would mean it was made in 1990, but I expect if I look more closely that’ll be a Q and mean it’s ‘92.

I’ll do a detailed list of the parts and build dates.

Correct. The pros were using it in late 91 at the September world champs in Il Ciocco, Italy, and I rode a demo bike at the event with it on it. It wasn't launched to the public until 92 and my Zaskar LE came with it. See Tomac's bike from the event:

 

[Matttymm]

I’m gonna have to go a find and check another now! I suppose the only way to know if the cogs were mismatched would be to check a NOS boxed one, which I don’t have.

I’ll have a look at home when I get there. Let you know.