Was intrigued so looked at the video slowly - looks crank/chain ring based with a pod type device[/img]

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http://opensourcetriathlon.blogspot.com/

Rumors are multiple options.....

Good Catch!

Powertap with Crank Based units & end-user slope adjustment = WIN*

*If priced competitively

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I wonder if it's related to this:

http://forum.slowtwitch.com/...ring=patent;#3479000

http://www.google.com/patents/US7975561

jaretj

Or could be this?

There's a powertap hub in that pic as well. Running multiple powermeters at the same time?

There's a pod sticking up from the left pedal in that still shot. Unless that's a speed/cadence sensor attached to the chainstay.

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Zen and the Art of Triathlon. Strava Workout Log
Interviews with Chris McCormack, Helle Frederikson, Angela Naeth, and many more.
http://www.zentriathlon.com

Another good catch! Maybe 3 ways possible?

Wasn't a prototype of this shown at interbike:

http://www.dcrainmaker.com/...lopment-company.html

to me it looks like the spider on the crank isn't being used. it looks to be a direct mount "power ring".

That was my first thought too, but looking at the angle of the crank in relation to the pod I think it's just a speed cadence sensor.

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Powertap / Cycleops / Saris

That looks like a speed/cadence sensor to me.

One reason if they are in fact running multiple PM's to is to check how accurate/reliable it is to what ever PM's are on the bike.

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

Looks like it might be a chainring power. Cool! Hopefully they're made out of melonited 4130 though O_O

The patent link above states the following below, basically a self installed end user power meter on your own crank:

It is therefore an object of the invention to provide a crank set based power meter.

It is another object of the invention to provide a crank set based power meter than can be used with the existing crank set of a bicycle.

It is another object of the invention to provide a crank set based power meter than can be installed by a non-professional.

Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.

based upon my reading of the patent, the pod you see is a speed/ cadence sensor, needed for the power calculation, torque x angular velocity/time. This is a very neat device and seems to cover many of the short falls of other devices, and probably comes close to an SRM or other crank based power meter. Since it is attached to the chain rings it will be able to determine left/ right balance as well based upon the knowledge of the cadence sensor location of the left pedal. If they can make it cheap enough this could be a game changer since it looks and is supposed to be easy to install on any crank system without throwing away or changing any current parts. Can't wait to see what they have in final form.

great link/article for those unfamiliar with the power tap history

the research articles provided are from 2004, 05 & 07. just curious if there is any data vs SRM more current.

That would be "pseudo-balance".

ain't it all ;-) when the force hits the chain ring if comes direct from the pedal through the crank arm and spindle, barring this bit of torsional flex in the crank arm and the spindle.. the sine wave of the force curve would relate to the left right balance would it not? Any how it would or could provide that data theoretically assuming they correct for this flex. Most accept the computrainer left/right balance that appears at the rear wheel? and assuming pedal sensors are duplicates of each other then they too could be psuedo left/ right balance as well? anyhow all in all this looks like a nice thing from power tap and I look forward to seeing what it looks like and costs and can do.

No, it all ain't.

Relate yes, be accurate, no.

I'll take that as a question and not as a statement. I don't think we know the answer to the question of what most think. I suspect most people don't realise what they are looking at. But left-right balance it is not.

Me too, although I'm struggling to see what this brings to the already over crowded small table.

That, too, would be "pseudo-balance" (same for what the Quarq provides).


Dual-sided power meters (e.g., Rotor, Garmin, Verve...and now PowerTap pedals?) enable determination of true left-right balance.


Speaking of costs, balance, etc., I suspect that PowerTap's hierarchy will be:

1) hub-based power measurement, for those on a budget;

2) crank-based power measurement, for those who want to use their own wheels; and

3) pedal-based power measurement, for those interested in a deeper understanding of how they pedal (and/or are unwilling to replace their present wheels or crank for some reason...similarly, the crank-based product is an option for those who aren't, e.g., willing to give up their Speedplay pedals).

and your particular choice would be_________ based on _________?

Thanks.

def waiting to see what they have!

the more player on the market the better we are :D

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The entire event (IM) is like "death by 1000 cuts" and the best race is minimizing all those cuts and losing less blood than the other guy. - Dev

If I'm paying for it myself? Probably #2 (assuming, of course, it's as reliable, precise, and accurate as an SRM, but less expensive than #3).

OTOH, I'm always happy to use any powermeters that are loaned/given to me (well, as long as they can be used alongside a system I trust, at least until they prove themselves).