What are the options for power measuring on the Sram XX1-group?

Possible ways i know of and fitting issues (i know of) with the XX1-group:

SPIDER (SRM, Quarq, Power2Max and similar)
- New BCD of 76mm and it seems like two arms also is a bit offset?! Should be possible to retrofit a new spider with power measurment or buy a complete crank with replaced spider.
- No measuring spiders available for the moment. Quarq is the best guess for the moment since the company is owned by Sram.
- Anyone heard some rumours?

CRANKARM (Stages Cycling)
- New option from Stages Cycling coming soon.
- Measuring device mounted on left crankarm. Sram X9 available.
- Will the XX1-spider fit the X9 crank?
- If it does, then this is the best option for now

BOTTOM BRACKET (Ergomo)
- I've only heard of Ergomo and that is a (old) bottombracket-standard with a splined axle included.
- Won't fit XX1-crank
- No other cranks with BCD 76mm available (yet)

REAR HUB (PowerTap)
- XX1-cassette requires a special XD-body.
- Anyone heard of retrofit XD-body's for PowerTap?
- One more problem (for me). I will use a solid X-12 axle, so the standard PowerTap hub will not fit (9mm axle)
- WheelBuilder.com has a X-12 conversion kit for PT-hubs for $175

PEDALS (Garmin, Polar)
- Will work i guess, but seems like a bad idéa for MTB. Very easy to hit rocks and so on and thrash the pedals very easy.

MORE OPTIONS
- Any idéas?


Updates in Italic text style

Since SRAM owns Quarq I bet thy will make an XX1 Quarq.

I would not buy a XX1 group just because too many different standards by now.
Own crank, own hub does make your current bike nearly unusable for swapping over parts/wheels.

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Experimental Prototype

Or just run a 'single' chain ring with upper chain guide for the time being so you can use a standard SRM/Quarq etc.

Really not sure why this is such a dilemma?

Not a dilemma. Just want to try the XX1-group with a power meter. Running a SS-ring + guide since a few years now. And i really like the simplicity of the system, but in some occasions i run out of gears = XX1. Thats all...

How about use for example Specialized crank with XX1 spider with XX1 ring,Sram type 2 rear mech and 11-36 cassette?? I think there will be some conversion kit for 10speed cassettes to build 11-42 versions.

That's what I mean - that it's not a dilemma if you're already running a good single ring and guide on a p/m crankset. You should just keep it

It wouldn't surprise me if a light single ring and really light chain guide are actually lighter than the XX1 ring, especially if their road rings are anything to go by.

The XX1 tooth profile seems like a great idea that is likely to help in extreme cross chaining situations but lots of people have had 1x 8/9/10/11 running pretty well for a while now. I imagine the minimal extra width of the cassette isn't really going to cause any more of an issue than it has in the past.

Thanks to everyone for your input!

I'm sure the Specialized (Lightning) crank + XX1-spider would be great (Kulhavy use it now on his golden bike), but it doesn't answer my question i'm afraid. The point here is not the best 1 x 10/11 drivetrain out there right now, it is how to measure power with the XX1-group.

I will build up a new 27.5" or 29" hardtail this winter and i am thinking about to try the XX1-concept without mixing parts (at first at least ). And i also want to continue logging watts on a power meter. I will keep my 26" full suspension bike with 1x10 drivetrain and a PT-hub for power data and to compare bikes / wheelsizes. And since i've trained with power as reference for almost five years now, i would very much like to keep logging power on the new bike also. And it might end up with a "normal" 1x10 drivetrain, but before that decision is made. I wanted to find out the options with XX1.

For now it seems like my hope stands to Sram/Quarq. But i'm not in a hurry. The bike is supposed to be finished at next spring at first.

At the moment I don't think there is a way to get power with the full XX1 gruppo. You could always go with XX1 in the rear and just ditch the XX1 chainring for a normal 1X ring to allow yourself to use a powermeter that's currently available.

you could use the new stages x9 power meter crankarm with the new xx1 chainring.

I'm sure quarq will be releasing a power meter soon enough.

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Trek 5500 - 13.75lbs on a $1400 Budget
20 gram 1x10 chain guide

Great news, just read about those yesterday. Very interesting option and not expensive. More information at Stages Cycling

Does anybody know if Sram is using the same spider mounting-standard across the entire MTB-line, or atleast on the top level? Thinking of X9, X0, XX and XX1.

And if Sram is using the same axle-standard for X9 BB30 cranks and XX1 BB30 cranks, then i guess one could mount only the left X9 crank (with Stages power meter) and keep the rest of the XX1 crank with the spider on the right? Will get a bit ugly if one cares about looks on the bike. And most of us do i think. Maybe also feels a bit strange with one alu-crank and one carbon?! If they are interchangeable, then i could switch to the complete XX1 cranks very easy whenever needed.

Will look better to run the X9 cranks with the XX1-spider as blantonator suggests i think.

The stages product looks pretty nice. The price is very reasonable as well. Too bad they don't have any carbon crank arms...

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Trek 5500 - 13.75lbs on a $1400 Budget
20 gram 1x10 chain guide

XX1 crank arms are made of carbon
http://r2-bike.com/sram-kurbel-XX1-1x11-BB30

Price is not bad,but remember that you have to buy rear wheel and thats another 950E

Yes, i know XX1-cranks are carbon (wrote about that in my last post). Just tried to list possible solutions/idéas with the Stages X9 left crank. I got the wild or stupid idéa to run a X9-crank on the left from Stages with the XX1-crank + spindle on the right. Will not look very nice though...


I will build up a new bike from scratch, including a wheelset with a XX1-body. There is already retrofit bodys available for most DT Swiss hubs and wheelsets. And at least AM Classic, Extralite, Hope, Mavic & Tune will also release a retrofit hub with the XX1 standard this fall/winter.

UPDATE: Tune will also release an XX1-body early 2013.