kurt kinetic power meter

You know I was just about to ask the same question - I have the kinetic road machine so I was thinking of the power meter. Anyone have any details on how it works. It seems to hook up to the back wheel of the bike so how does it pick up the power put into the kinetic unit?

Cheer

J

Here's a link on the power meter and the details of how it works:

http://www.kurtkinetic.com/computer_tech.php

the KK trainers have a progressive, predictable power curve based on the relationship between speed and resitance that is measurable by their computer. Recently there was a thread on Slowtwitch about the accuracy of the meter, which sounded like up to a sustained 400 watts or so, it was fairly accurate as compared to power meters. The KK websire claims a +/- 3% when compared to a Power Tap.  Not bad for around $50, eh? 

I have the unit and it works. It may not be as accurate as a power meter, but the results that it puts out are consistant and therefore of value for measuring progress over time and for me, +/- 3% is plenty accurate enough.  

Great, cheap way to actually measure your power progression and improvement.

Thanks for the info. I just ordered one online for $35.99

J

Kurt Kinetic publishes their power curve so it is a pretty simple matter to convert MPH from the bike computer to power.   I believe most people do the calculation in their heads to take some of the boredom out of riding the trainer.

From their tech tips.

http://www.kurtkinetic.com/powercurve.php

Kinetic Road Machine Power Curve:
P = (5.244820) * S + (0.01968) * S*S*S

For example, to calculate how much power is produced at a speed of 16.1mph while riding the Kinetic Road Machine, plug 16.1 in for “S.”

P = (5.244820) * (16.1) + (0.01968) * (16.1) * (16.1) * (16.1)

P = 84.4416 + 82.13017

Power = 166.571 watts

They have a chart that gives the approx watt output at any given MPH from 1-50. Click the link and scroll to the bottom of the page: http://www.kurtkinetic.com/documents/Power_Curves419.pdf

Wouldn't you rather have the power to 6 decimal place.  Besides what else do you have to do while riding?

TW

I have one and use it with my KK trainer. Here's the major difference between it and a true Power Meter. If the rear wheel is spinning, its registering watts whereas a PM measures the power you're putting to the wheel. If you're freewheeling, its 0 watts. Not sure how big a difference this makes vs. a true power meter but note that it won't necessarily be an accurate reflection of power as defined by those using power meters.

Cheers!

TM 

Ha - I never free wheel on the road machine!

Yeah right - as if!

 The KK Road Machine is awesome.  The power meter works but as for the power meter's quality... It sucks. It's Cheap it has crappy buttons. It uses a weak heavy magnet instead of using a Neodymium Iron Boron (NdFeB) magnet that would cost 5 cents and would of been 1/10th the weight, high failure rate on the computer,  cheap wire,  easy water impregnation. Odometer and memory issues. Bad button layout. Really weak retention clip. Seriously, It cost $1 to make and its junk but for $40-$50 it's accurate and cheap compared to a PowerTap. So while I hate it it's also 1/20th the price of something a few % more accurate.