Kinetic Inride 3 vs ZPower on Road Machine


(Terry) #1

I am thinking of getting an inride 3 sensor and wonder how users are finding the power compares with ZPower and classic power.
The power curve for the road machine shows about 240 watts at 30kph. In Zwift scenarios with zero gradient I typical get between 160 and 170 watts with ZPower at that speed.
I have read other posts indicating that ZPower actually over estimates output when compared to a power meter so can I expect even less output using the inride 3?
Having difficulty understanding this as it seems inconsistent with KK’s power curve.


(Z Kryder) #2

Zwift is w/kg to determine speed. I have the KK and with zpower was about 35 watts too high compared to most accurate power meter.
The chart Kurt provides is only a comparative chart.
Here’s what they say:

In Depth: The Science Behind the Power Curve

1. We started by defining the “average rider”

We created an “average rider" assumed to be:

  • 165 lbs.
  • Riding a 23 lb. bike
  • With 170 mm crank arms
  • Up a 1% grade
  • At sea level
  • With no wind
  • On rough asphalt

The “outdoor ride” that we reference on the comparison chart above is based on this “average” rider’s predicted profile using complex calculations of a variety of forces that interact with all outdoor riders including: rider weight, bike weight, atmospheric density, and other less obvious forces like frontal area.

Blockquote


(Terry) #3

The interesting thing is that both Zwift and Kinetic say they stand by their power calculations but they cannot both be correct. If ZPower is 35 watts too high then at 30 kph I am putting out only 125 to 135 watts when Kinetic says I am putting out 240. That is not a small discrepancy.