Someone's listening!

Interbike is always interesting with all the forward-thinking cycling minds converging in the Nevada desert.  Such a bikefest, yet I've never been there....hmmmm....

Anyway - my ear is always to the ground listening for the latest and greatest from the cycling industry.  I must admit that power meters are an area where I'm most interested.  The physiological side of cycling (and maximizing it) is king in my book, and for cycling, there is no better tool than a power meter to guide one's training and performance analysis.

The flip side of power meters is complexity.  Generally speaking, they are a pain the ass for mountain bikers.  We are faced with the dilemna of "which bike" to set up with power, the MTB or road bike?  I have 8 bikes  now, not just two - some 26" mtbs, a 29er mtb, and a couple of road bikes.  Some of the mtbs are disc brake only in the rear, meaning the PT is a no go - and I've already got 3 of them.  Then add the hassle of keeping the wiring harnesses working on the bikes that will accept the PT and it gets even worse...Getting the picture?   PITA.

Enter MicroSport Technologies.  They've come up with a perfect solution to my nightmare - they've been listening!  For a number of years I've periodically tossed out the notion that it would be great if some enterprising inventor would develop a power meter based on either force actuated pedals or shoe insoles.  Now I have no clue if MicroSport actually heard my ramblings, but hey, they've gone and done the latter, the magic slippers of power meters. 

It's a very simple system:  force measuring insoles; a 2.4 GHz wireless transmitter that clips to the shoe; bike computer.  I'd assume there is also a speed sensor in there somewhere, but it doesn't appear to be listed.  The product literature does say that it is compatible with 2.4 GHz ANT compatible hardware/sensors - the Polar comes to mind there, but cross-manufacturer compatibility? 

They did a bit of homework to figure out the forces a rider puts on the pedals in 3 different modes - seated, low cadence seated, and standing.  Below is a graphic representation of how the results of one of these cases might appear.  The dotted line represents the crank, the straight line at the end is the pedal orientation, and the arrow shows the direction the force is applied while the length indicates the relative magnitued.  

This is key to the design since the normal force at the pedal is required to calculate power.  Supposedly the algorithm can detect when the rider is in any of the 3 positions and uses that specific known relationship.

The end result?  They claim +\- 5% accuracy, and +\- 2% repeatability.  It's completely electronic - no hubs or bbs to wear out, no equipment changes, and works in any condition (completely wireless).

Cost?  Well...pre-order now and it's $500.  I have...and no, I have zero affiliation with these folks.  But this is the coolest thing to come out of interbike in a long time.  It's not a novel *idea*, but to implement and market it - I am so impressed, and pretty excited too.  It would mean the end of TSS estimation and will probably be the lightest PM on the market to boot.

On the flip side, the wattage listers poo poo'd it pretty hard, mostly because when sprinting you do lift up on the pedals, and this upward force can't be measured by this system.  If you want hard numbers for sprint workouts, thats a good reason to go with the other PMs...but for me?  I only sprint out of the saddle when chased by dogs.

They are not yet ready to ship the units, but when they do, I'll give it a thorough testing, comparing with the power tap ala Robert Chungs Rosetta Stone files and post findings here.  Until then I'll just keep swapping out my wheels ;)

Published Friday, October 06, 2006 5:03 AM by Dave


# @ Friday, October 06, 2006 6:25 AM

Day's after I purchase an ergomo they come out with something better. Doh!


# @ Friday, October 06, 2006 10:30 AM

I wouldn't say the MicroTech device is better - not yet anyway. Once I run it through my testing mill, then I'll be in a better position to say...but for now, the Ergomo is a safe bet that works for disc only MTBs - and has TSS/IF/PNORM built in. Hard to top that I'm thinking...


# @ Friday, October 06, 2006 11:08 AM

I put my ergomo on my road bike. I was holding off on purchasing a second bottom bracket for my mountain bike. Maybe I can get a Microtech for my mountain bike if your testing goes well. Would be cheaper than a second bottom bracket anyway.

How you do estimate TSS on days when you don't have your PT? I have seen some graphs that plot TRIMP like numbers against TSS. Then they do a linear curve fit on the plot and back out TSS numbers that way.


# @ Friday, October 06, 2006 11:43 AM

Estimating TSS - that's a post all in itself. Maybe I'll get to that some time...but basically, I use the PM as much as I can. This gives me a good sense of what sort of IF I'm going on any given ride. Then, when I don't have the PM, I estimate IF and calculate TSS = IF^2 * time (hours) * 100. At least that's what I do sometimes. Other times I just wing it - pretty easy to do for a ride in familiar terrain for which you have a bunch of recorded times & TSS values.


# @ Friday, October 06, 2006 1:20 PM

Thanks Dave. What you have done this year is amazing. Thanks for posting all this information on your blog and helping the rest of us out. Hope you have a great race at Moab!


# @ Friday, October 06, 2006 11:45 PM

Hummmm that would even work with a fixie or mabe the back pressure druing braking and slowing would give a strange reading... Dave you and LW are proof positive that power meters and that type of train work very well =)

I think I am interested in keeping it a little more simple


# @ Saturday, October 07, 2006 5:31 PM

I just hope I don't have to stick my insoles on my desk to download,l phew...

- Rich


# @ Saturday, October 07, 2006 5:37 PM

Actually, have you spoken with them? There website doesn't seem to mention download capability at all (that I can find).

- Rich


# @ Monday, October 09, 2006 6:38 AM

I read about this last week and I'm thrilled you're going to guinea pig this for all of us who sit idly by waiting for a moderately priced PM to hit the market. This attempts to fill the huge hole in the PM market, a hole Polar has tried (and apparently failed) to fill. This is even cheaper than the Polar model.

"It would mean the end of TSS estimation and will probably be the lightest PM on the market to boot."

To shoe? Sorry, that's awful.



# @ Monday, October 09, 2006 12:34 PM

By the way, do you know when this is supposed to be available?


# @ Monday, October 09, 2006 3:08 PM

Norm, check out my latest post for answers to that and many other questions...