e*thirteen TRS cassette

[RS VR6]

If you have an XD compatible wheel and want to switch to 1x...this may be the cassette to get.

The 11sp version is 9-44 and the 10sp ver is 9-42.

I have a 30T with a 11-42 10sp Response cassette. With the e13 cassette for example, I can drop to a 28T and have more low and more high than with my 30T/11-42. Seems like a win, win situation when it comes to gearing. The other benefit is the cassette is modular. It comes in three parts and the three parts can be purchased individually as they wear. 

I have no idea on cost (lol...that can be the killer ). I haven't the cost posted anywhere. Should be available by the end of the year or early 2016.

http://bythehive.com/e-thirteen/components/2016-trs-cassettes/

[xcbarny]

One thing to be aware of, is that smaller sprockets create more friction that bigger ones, and so are harder to turn.

Just try with your bike in the workstand, pedalling with no resistance, somewhere in the middle of the cassette, say 5th or 6th.
Then shift into top gear (11t) and feel the difference in resistance.

Theoretically, it should feel near enough the same, but the load is much higher when in the 11T. I think extra friction is caused by there being more load on each tooth / chain roller, and the chain having to bend at more of an angle around the smaller sprocket.

Some info here:
http://cyclingtips.com.au/2010/04/the-big-ring-mechanical-or-psychological-advantage/

[RS VR6]

From what I've read is that the smaller the cog or chainring...the more load on the teeth. This could be the reason why the 28T XX1 chainrings wear faster than the rest. I majority of my pedaling time is spent in the middle to upper part of the cassette. Only time I use the lower part of the cassette is when I'm descending and not pedaling much. The e13 cassette's smaller cogs are smaller than what I got now.

I'm going to wait till I see a few real world reviews before I jump on one. At ~280usd for the 10sp...I can wait. 

[Vipassana]

This looks promising. 

I was speaking to the SRAM engineer/rep at a race this summer and I asked him when the 44T 11 spd cassette was coming.  His response was to laugh and tell me he couldn't confirm or deny it's existence, but then said but if it were to come, it would be in 2016.  I would buy one if it is compatible with my current X01 rear derailleur.  Then I could throw a 34T on the front and have more top end speed, which I need now.

The 9T on this makes me nervous.  That adds a lot of stress on the teeth and chain.  The current XX1/X01 is a 10T and when I'm in that gear, I can feel it grinding.  It is noticeably rougher than an 11T or bigger sprocket.  I'd be very concerned that a 9T would wear prematurely (itself or the chain) or sound terrible while riding.  And to make that from aluminum... that's going to not last long.  I read somewhere, but cannot find a source, that the 10T is basically on the verge of the design limits of the pivot spacing on the chain.

Give me a 44T-10T and I'll be happy.

[RS VR6]

SRAM said that the 10T is the smallest you can go without having the "polygon effect". I think it's somewhere along the lines of the chain not being able to maintain a smooth arc around the cog. I have no idea since it's something I've never had any experience with. At least for me, the 9T will be something I spend very little time in. As of now...my 11T is something I don't use often. Only time I find myself using the 11T is long stretches of downhill...in which I'm coasting the majority of the time anyways.

Just waiting on the reviews to trickle in before I jump on one...or not jump on one.

[xcbarny]

Works for sproket and the chainring, so a 48:28 combo would run smoother than a 24:14, even though its the same gear range.

And yes a 28T chain ring is going to wear faster than a 32T. I guess its a bit of a trade off for running a 1x sutup. And if a 28T front is what you need for your hills, then there isn't much else you can do about it.

As you said the small sprocket, be it 11t or 9t, doesn't get a great deal of use, and rarely in a situation where it needs to be efficient - ie downhill. The one place I do notice it, is trying to keep up with guys with a 44 or 42 T big ring, on the road.

[cmh]

SRAM said that the 10T is the smallest you can go without having the "polygon effect". I think it's somewhere along the lines of the chain not being able to maintain a smooth arc around the cog. I have no idea since it's something I've never had any experience with. At least for me, the 9T will be something I spend very little time in. As of now...my 11T is something I don't use often. Only time I find myself using the 11T is long stretches of downhill...in which I'm coasting the majority of the time anyways.

Late reply here, realized I've been out of touch for a while.  SRAM says under 10t you get the "polygon effect" - I remember Shimano doing a test back in the '90s - I think - where they actually tested drivetrain losses and said it becomes significant under 16t! Still, tiny rear gears are necessary with small front chainrings, and those make sense for maximized clearance. I was a bit insulted when my Epic came with a 30t chainring, figure an XC bike is all about big-gear mashing, but was glad to have the 30/42 in the surprise snow today. The 10, I barely use it, but did manage to hit 32mph on a twisty shared use path spinning out that 10 the other day. Off the road, I don't think I go that high that often because most of the downhills around here are technical enough to keep speeds in check. So yeah, same here.

Still, options are cool.

[Carbon_Dude]

I could see changing out my 32T chainring for a 34T and a cassette with a 44T cog for more top end while keeping a good ratio for climbs, although I'm not unhappy with the current 32T/10-42 standard XX1 setup.  I know my drivetrain is getting some wear and will most likely need some replacing soon but I will probably just put a new chain and chainring on thinking the cassette is probably still good for a while longer.

[kingchickenstrip]

I have been using this cassette for a fer months now and love it! It's so nice to have the top speed back! It shifts just as good as the XTR cassette it replaced. I use the 9 and 10 tooth for down hill and single track all the time. I am not standing up mashing on the crank when I am in the 9 and 10 tooth. It's really nice to keep my speed up so when I am approaching another hill I can ride up most of it before I need to shift. Single track sections that were once bumps are now jumps and I find myself using my brakes more. I finally have a 1x that is not a compromise!

[carbonazza]

Thank you for reviving this post.

Although it is quite more expensive and marginally heavier than the XX1 cassette.
I'm done with changing the whole cassette just for a couple of worn out sprockets.

After wearing out two XX1 cassettes in less than two years,  I'll switch to an e13.