fkelly
03-20-2014, 02:43 PM
To avoid hijacking the Stages delivery thread http://forums.thepaceline.net/showthread.php?t=145290&highlight=stages+power, I'll start this. Received my Stages Power Meter two days ago (March 18, ordered on February 2). I prepared for installation by reading and re-rereading the DCrainmaker articles on the subject. Still got caught a bit short: he was using a SRAM crank and I didn't realize that removing a Dura Ace crank necessitated using a special tool. Luckily my local bike shop was open and had the tool and did the necessary work for me. Other than that, the process was about as simple as DCrainmaker says.
Been out for two cold rides now. The Stages is paired with a Garmin 800. Power shows flawlessly. Previously my process has been: upload the rides from the Garmin fit files to Sporttracks. Use the weather plugin to get weather estimates. Then use the power plugin to estimate (calculate Power). Then export the whole file to a TCX and upload to Ridewithgps. That way I have my files stored in two places and can use ridewithgps superior analysis and review tools.
One question I wanted answered was "how does measurement of power compare to just estimating it?" The attached images answer this. The first image is the Sporttracks estimate of my power. The second is the Stages measurement. To get the scales of the graphs to be fairly consistent I had to delete one 500+ watt power calculation from Sporttracks at about the 2 mile mark. One difference is that Stages automatically drops off to zero power when you stop pedaling. There is an adjustment I can make to the Sporttracks file to simulate this but it still shows some power even when you aren't pedaling. My average power in Stages was 103 watts and the max was 302. In the calculated version these values are 89.5 and 297 respectively.
Both days that I've ridden with the Stages have been cold and wet: low 40's degrees with sleet one day.
For what it's worth, on indoor gym devices (Startrac upright bikes) I pretty much average around 200 of their measured Watts. How well they are calibrated is another question: my experience is that there is at least a 10 percent difference between the three upright bikes at my YMCA but that a given bike is pretty consistent between rides. We'll see how this compares to the Stages when the weather improves a bit back East here.
Been out for two cold rides now. The Stages is paired with a Garmin 800. Power shows flawlessly. Previously my process has been: upload the rides from the Garmin fit files to Sporttracks. Use the weather plugin to get weather estimates. Then use the power plugin to estimate (calculate Power). Then export the whole file to a TCX and upload to Ridewithgps. That way I have my files stored in two places and can use ridewithgps superior analysis and review tools.
One question I wanted answered was "how does measurement of power compare to just estimating it?" The attached images answer this. The first image is the Sporttracks estimate of my power. The second is the Stages measurement. To get the scales of the graphs to be fairly consistent I had to delete one 500+ watt power calculation from Sporttracks at about the 2 mile mark. One difference is that Stages automatically drops off to zero power when you stop pedaling. There is an adjustment I can make to the Sporttracks file to simulate this but it still shows some power even when you aren't pedaling. My average power in Stages was 103 watts and the max was 302. In the calculated version these values are 89.5 and 297 respectively.
Both days that I've ridden with the Stages have been cold and wet: low 40's degrees with sleet one day.
For what it's worth, on indoor gym devices (Startrac upright bikes) I pretty much average around 200 of their measured Watts. How well they are calibrated is another question: my experience is that there is at least a 10 percent difference between the three upright bikes at my YMCA but that a given bike is pretty consistent between rides. We'll see how this compares to the Stages when the weather improves a bit back East here.