AeroPod, PowerPod and Newton

I have been using my unit on my road bike for about 6-8 weeks and thanks to coachboyd it seems right on as far as power numbers go while climbing. I have noticed that the numbers seem really low when going on slight downhills or steeper. Not sure how I can tell what to adjust to give me a more accurate downhill wattage. Coachboyd if you can look at it again I would appreciate it. My RPE is way to high for the low power numbers I am getting on these slight to moderate downhill sections...., than again I could just be going crazy. Also if something needs to be changed will affect the numbers when climbing? This is not an out and back ride, but I did go back and forth around 1/3 of the way into the ride where there was an avg 2% or so grade climbing and then descending in the other direction.
Thanks....

Clint

Have you changed anything from the summer profile (like wearing a jacket or a lot more clothing?). I had noticed that the temperature was at 44 degrees and if you are wearing more clothing your cda will be higher. Going down hills this added clothing will slow you down some which will result in lower watts if you have the same cda in the profile.

With the new software it's very easy to adjust this. Go into the profiles and push "hold" on the wind scaling. You can now adjust the aero coefficient up a little bit and the cda will raise. I would estimate you will want to take your cda up by about .017 to .02 (added to your current .368)

I had read somewhere in the forums that you can go to the coast screen and go about 20-30 mph coasting and I should get close to zero watts. If not then you can adjust the numbers as you said. Will this work??

And yes I did have a light jacket on but I have noticed this even before when I was just wearing my normal riding gear. It became more apparent as I was doing some endurance and tempo rides and could not hold the power numbers at around 200 or so for 2 hours except on the climbing portions of the ride even though I was hammering it. Anyways thanks again...


Clint

GWPOS wrote:I had read somewhere in the forums that you can go to the coast screen and go about 20-30 mph coasting and I should get close to zero watts.

That is correct... assuming that your tilt is right. Another possibility is that your hand position and weight shifts on the downhill and your riding tilt changes enough to cause the error. Frankly, I wouldn't worry about downhill errors unless they are consistent and fairly large... then a tweak might be in order.