# XTR cassette weight savings over XT (11-32)



## notenoughtime (Sep 7, 2004)

I'm looking at the new line of cassettes, 970s and 770s. From what I read, the weight difference seems to be only about 10 g or so. Can people comfirm this?


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## Duckman (Jan 12, 2004)

That is correct. The reason its not any lighter is because the XTR 11-32 uses 5 arms. The XT 11-32 uses 4 arms(I have both cassettes). Thats why the $59(and then get 10% off that lots of times) sale 11-32 XT cassettes aren't bad deals. 

loose 10 more gms(=250gms) by using an alum lockring.


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## notenoughtime (Sep 7, 2004)

Duckman said:


> That is correct. The reason its not any lighter is because the XTR 11-32 uses 5 arms. The XT 11-32 uses 4 arms(I have both cassettes). Thats why the $59(and then get 10% off that lots of times) sale 11-32 XT cassettes aren't bad deals.
> 
> loose 10 more gms(=250gms) by using an alum lockring.


So would the 5 arm XTR be stronger? I hear so many horror stories about the large rings bending.


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## Some Guy (Mar 27, 2005)

notenoughtime said:


> From what I read, the weight difference seems to be only about 10 g or so. Can people comfirm this?


I think you'll find it's a bit more than 10gr. M760 XT is 260gr (or 250gr with an al lockring) and M970 XTR is 222gr. I don't think the M770 cassettes are any lighter than M760.


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## Duckman (Jan 12, 2004)

Depends on the rider and if he knows how to shift. I've got 3 in service atm on 3 diff bikes. One of those is from 03. Never bent one to date.


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## kster (Nov 15, 2007)

I don't know how accurate these are but coloradocyclist.com lists them at:
XT M770 11-32: 295g
XTR M970 11-32: 224 g


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## Some Guy (Mar 27, 2005)

kster said:


> I don't know how accurate these are but coloradocyclist.com lists them at:
> XT M770 11-32: 295g
> XTR M970 11-32: 224 g


That M770 weight is for 11-34, not 11-32.


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## kster (Nov 15, 2007)

Some Guy said:


> That M770 weight is for 11-34, not 11-32.


That makes much more sense; it explains the large weight difference.


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## notenoughtime (Sep 7, 2004)

Some Guy said:


> I think you'll find it's a bit more than 10gr. M760 XT is 260gr (or 250gr with an al lockring) and M970 XTR is 222gr. I don't think the M770 cassettes are any lighter than M760.


I guess these weights are probably most accurate.


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## nino (Jan 13, 2004)

*weights...*

XT 11-32: 263g including steel lockring (save about 10g with a aluminium lockring)

XTR 970 11-32: 223g

as we all know only the larger sprockets of the XTR are titanium. i just replaced the remaining steel cogs of the XTR with the same size Titanium cogs of my own Ti-cassettes and the result isn't all that bad: 189g 

shown below:
XTR 970 11-32: 223g
xtr steel cogs/spacers
Nino's replacement Titanium cogs/spacers
tuned XTR 11-32 cassette with Nino's titanium cogs: 189g


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## Duckman (Jan 12, 2004)

I remember now my 11-32 XTR is the 960. My bad. 

I really like the add-on cogs for 189gms. 

That is all.
Duck


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## Some Guy (Mar 27, 2005)

I'm thinking the cassette wouldn't last as long though. There is a reason those cogs are steel.


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## ovidiugm (Mar 30, 2007)

If you don't climb really steep hills, you could just go with a Dura-Ace CS-7700 in 12-27.
Should be under 180g .

Unfortunately I wasn't able to find a 20T granny for my XT crank, but there are some out there available for other types of cranksets - just to keep your ratio as close as possible to 22/32.


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## Fast1 (Apr 6, 2007)

ovidiugm said:


> If you don't climb really steep hills, you could just go with a Dura-Ace CS-7700 in 12-27.
> Should be under 180g .
> 
> Unfortunately I wasn't able to find a 20T granny for my XT crank, but there are some out there available for other types of cranksets - just to keep your ratio as close as possible to 22/32.


that is the exact route I took except with a 11-23 Dura Ace.. but I'm in the midwest of the USA without any major mountains to ride nearby.

Another plus with the Dura Ace 11-23 is more appropriate gearing for pavement/snow pounding during the winter months.


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## Duckman (Jan 12, 2004)

Used an 11-27 Duraace(added the 11t) for about 3 race seasons. Ran a 42-30-20t setup. The problem isn't the granny. The problem is the middlering. Since I'm in the SE mtns, with the 11-27, I had to go to the granny way too often for my taste. Plus massive chainsuck was experienced with the 20t a lot of times. Now back with an 11-34XTR, I never go to the granny(back to 22t's) for an XC race. Only on bigger stuff like ORAMM(11000' vertical/63 miles), etc do I ever need to go to the granny. The FD is the weakest link to a given bike and every time one goes to the granny your exposing one self to the chance of a dropped chain, chainsuck, etc plus they sometimes won't shift under power like when your too late dropping down into the granny(which happens alot with a road cog and in mtns) because your oxygen dept'n in a race and forget(one more 'big' extra thing to think about in the heat of battle). ymmv.


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## notenoughtime (Sep 7, 2004)

I can't handle a road cassette.  XTR or XT are the only options. Should I even look at the Sram 990? How's that weight compare in the 11-32 variety?


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## Fast1 (Apr 6, 2007)

Duckman said:


> Used an 11-27 Duraace(added the 11t) for about 3 race seasons. Ran a 42-30-20t setup. The problem isn't the granny. The problem is the middlering. Since I'm in the SE mtns, with the 11-27, I had to go to the granny way too often for my taste. Plus massive chainsuck was experienced with the 20t a lot of times. Now back with an 11-34XTR, I never go to the granny(back to 22t's) for an XC race. Only on bigger stuff like ORAMM(11000' vertical/63 miles), etc do I ever need to go to the granny. The FD is the weakest link to a given bike and every time one goes to the granny your exposing one self to the chance of a dropped chain, chainsuck, etc plus they sometimes won't shift under power like when your too late dropping down into the granny(which happens alot with a road cog and in mtns) because your oxygen dept'n in a race and forget(one more 'big' extra thing to think about in the heat of battle). ymmv.


Have you compared a 30/27 (31.1") ratio to a 32/32 (28") in gear inches.. not much difference, just about like shifting down from a 29 to a 32 cog in the back on a standard tripple set up. Don't understand why you allways needed to jump to the granny ring with such a small gear inch difference in your two set ups??

Appears you might need to adjust your FD inside limiter if you are dropping chains.. I've never had the problem on either my moutain or road bikes unless of course the FD is out of adjustment or the cable has stretched.


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## Duckman (Jan 12, 2004)

Never said I dropped chains. I said theres always that "chance". 

I run a 30/34, not a 32/32. Thats low enough for about anything at XC race pace. At least for a short but intense 1.5hr XC race. Some topend loss of course..but thats what the bigring is for. Longer races like the above mentioned, 12 hr solo's(on certain courses), etc still could require the granny sometimes tho.


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## nino (Jan 13, 2004)

*SRAM : 270g*



notenoughtime said:


> I can't handle a road cassette. XTR or XT are the only options. Should I even look at the Sram 990? How's that weight compare in the 11-32 variety?


from what i remember the SRAM cassette (the one with the red spider) weighs about 270g or slightly more. so 10g more than the XT.


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## Some Guy (Mar 27, 2005)

http://www.yourtrails.net/weights/listing.php?cat=18&subcat=52

990 weighs 265gr. So really not competitive with Shimano's offerings, especially when you consider that with the same lockring XT weighs just 250gr.


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## notenoughtime (Sep 7, 2004)

The 990 comes with an alum lockring right? If I get the XT, where's the best place to get my lockring?


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## Some Guy (Mar 27, 2005)

I bought mine from Toronto Cycles on ebay. It's an SRP model that has been in use happily for three years and many cassettes. I'm surprised by how long it has lasted to be honest.

Or you could hit up your LBS and see if they have any left around from dead XTR/990 cassettes.


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## Duckman (Jan 12, 2004)

I've gotten some generic alum rings from Cambria in the past for $4. Its been awhile tho.


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## thetschappats (Mar 27, 2007)

nino said:


> XT 11-32: 263g including steel lockring (save about 10g with a aluminium lockring)
> 
> XTR 970 11-32: 223g
> 
> ...


Nino,

Your cassette looks great, but it is a bit pricey... have you thought about selling the smaller cogs from your cassette seperately as a costs saving option to add to an XT/XTR cassette?

By the way... I think your posts on the forums are some of the most informative! Keep up the good work!


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## nino (Jan 13, 2004)

thetschappats said:


> Nino,
> 
> Your cassette looks great, but it is a bit pricey... have you thought about selling the smaller cogs from your cassette seperately as a costs saving option to add to an XT/XTR cassette?
> 
> By the way... I think your posts on the forums are some of the most informative! Keep up the good work!


sure - i have these smaller cogs to fit shimano cassettes ! i'm just waiting for the 13t cogs to arrive which were missing in the delivery i got. but that was my plan to have enough spare cogs for those looking to upgrade XTR cassettes.


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## nj0ywatch1np0rn (Mar 29, 2005)

not to barge in on the thread here but my questions is this: I have a SRAM 990 cassette and usually only use the smaller cogs. Can i replace just these cogs instead of the entire cassette?


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