Does the Dash rely on the iPhone's gyro for performing any of the power calculations?
I completed the calibration setup and the speed/cadence sensors seem to be working fine but I've noticed the power is all over the place.
I suspect it's the result of relying on the iPhone gyro, which if true is too bad as the iPhone gyro is still a very temperamental technology.
What about the calories expended? Does this also rely on the gyro in some way (a function of the power measurement?). Ive used Suunto HR monitors for years and have noticed the iBike calculations are WAY off what my SUUNTO readings are; some rides by up to 50% less.
Thanks in advance.
iBike Dash +Power
Re: iBike Dash +Power
Power output whilst cycling is stochastic by its very nature [1], and therefore will fluctuate considerably whilst training out on the road due to air density and the gradient of the road etc. However, if you are performing intervals on a turbo or rollers power numbers will be more stable as these variables have no impact.
Viewing calories expended from heart rate monitors will generally lend themselves to over inflated numbers as they are invariably a guesstimate from questionable formulas based on age, height and weight and therefore are not very precise in determining the effectiveness of a particular work out. The ibike's calculation of calories expended is far more reliable as it is determined by the energy expended in putting the power down through the pedals.
Nik
[1] read up on training with power material/articles written by Hunter Allen and Doctor Andrew Coggan.
Viewing calories expended from heart rate monitors will generally lend themselves to over inflated numbers as they are invariably a guesstimate from questionable formulas based on age, height and weight and therefore are not very precise in determining the effectiveness of a particular work out. The ibike's calculation of calories expended is far more reliable as it is determined by the energy expended in putting the power down through the pedals.
Nik
[1] read up on training with power material/articles written by Hunter Allen and Doctor Andrew Coggan.
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Rochambeau
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Re: iBike Dash +Power
Nik,
I appreciate your input but it's not really what I'm asking.
For one, I am very familiar the calories expended concept - as I said, I've been using the top end SUUNTO wrist fitness computers for years and they are VERY accurate with respect to those calculations. The fact that the iBike's estimations are up to 50% off for the same route/distance, etc. than SUUNTO is why I ask if that function is tied to the Power calculation.
The reason i ask about the Gyro and Power relationship is that there have been times that I have been on slight downhill sections and the iBike reads zero power output even though I am turning the crank with moderate force.
That, plus the power readings seem to fluctuate wildly when going into the initial ascent of a steep climb.
I just want to know if any of the iBike's calculations are based on the iPhones gyro; that's it.
I appreciate your input but it's not really what I'm asking.
For one, I am very familiar the calories expended concept - as I said, I've been using the top end SUUNTO wrist fitness computers for years and they are VERY accurate with respect to those calculations. The fact that the iBike's estimations are up to 50% off for the same route/distance, etc. than SUUNTO is why I ask if that function is tied to the Power calculation.
The reason i ask about the Gyro and Power relationship is that there have been times that I have been on slight downhill sections and the iBike reads zero power output even though I am turning the crank with moderate force.
That, plus the power readings seem to fluctuate wildly when going into the initial ascent of a steep climb.
I just want to know if any of the iBike's calculations are based on the iPhones gyro; that's it.
Re: iBike Dash +Power
An iDash plus power does not use the iPhone gyro in any way. The only use of the iPhone is for GPS data and to run the app. Wind, tilt, elevation and speed are all determined by the electronics of the "Phonebooth".
I find the calorie calculations spot on (assuming the unit is setup properly). Calorie are simply math crunching after power is determined. FWIW, I generally burn about 550 cal per hour on a brisk ride. That's me at 184lb and each person is going to be different. That said, 400-500 cal/hr for easy rides, 500-600 for brisk rides and 600+ is a real hammerfest for one hour. A one hour time trial for me at FTP 210 would be about 740cal. If you're seeing numbers 1/2 of these then something's wrong. I don't know how much you weigh or how fast you are so these will vary but you get the basic idea.
I find the calorie calculations spot on (assuming the unit is setup properly). Calorie are simply math crunching after power is determined. FWIW, I generally burn about 550 cal per hour on a brisk ride. That's me at 184lb and each person is going to be different. That said, 400-500 cal/hr for easy rides, 500-600 for brisk rides and 600+ is a real hammerfest for one hour. A one hour time trial for me at FTP 210 would be about 740cal. If you're seeing numbers 1/2 of these then something's wrong. I don't know how much you weigh or how fast you are so these will vary but you get the basic idea.
Fernando