uphill vs downhill

[tbrucebowers]

It really seems like my downhill power and uphill power readings are out of whack. My uphill power readings are higher than they "feel" and downhill just the opposite. I have attached my latest ride file. Hoping to learn a lot more about refining my PP.

iBike_08_16_2017_1000_16_Miles.ibr

(297.76 KiB) Downloaded 317 times

[Velocomp]

Your ride file suggests you riding a TT bike. Is this correct?

Your profile shows a negative number for friction. This suggests that your PP was calibrated in a different position.

I would set up your PP for another O&B ride, then before starting the ride make sure you follow the instructions to get the PP securely fastened in its mount.

Please post another ride file after you've recalibrated your unit.

[tbrucebowers]

Hi John thanks,

Yes, TT bike. I did a cal ride in TT position, and you looked at it. Your comments were:

1) His CdA is way too high for an aero position. For someone of his size, it should be about 0.24

2) His wind scaling is a bit high (too much air on downhills)

I adjusted his profile for both factors.

I have been tinkering with things, and may have altered things I didn't intend to. I'll do another O&B and get back to you.

[Velocomp]

OK

[tbrucebowers]

Alright, I did two cal rides, both with little problems, which may not matter.

Ride #1- I ran out of pavement, had to slow down drastically, and loose my aero position as I hit the gravel road. Turn around occurred in the short gravel section.
Ride #2 - Probably OK, but it had two turns, some coasting, and some braking. When coming to the stop in the middle, I sat up as I was coasting and braking.

A couple little PP O&B foibles I have noticed:

1) the 0-50 count sometimes goes beyond 50, and also goes to zero during the time it takes to turn around after stopping. Picks back up at 50 when I start the return.
2) the CdA seems to always revert to the "Hoods" setting of 0.361 during the cal ride, even when I specify the TT setting (0.264 I think) in the setup.

OK, let me know what you think of these cal rides, T Bruce

[tbrucebowers]

Here are the cal rides...duh

[tbrucebowers]

Hi John, I don't know if you missed my cal ride posting (just before this) or you just busy with other things. Just checking in because it's been a little longer than usual for your response.

Thanks, T Bruce

[tbrucebowers]

Addendum

My PP is mounted very securely, and I never remove it. I will do a regular ride tomorrow based on my latest cal ride, and submit the file. Unless you tell me the cal ride is wonky. I do know the profile that was created has the high CdA that you fixed last time.

T Bruce

[tbrucebowers]

OK, ride is done. I have attached the last cal ride file, the current ride file, and a photo of the PP mount.

FYI the profile is the one generated by the cal ride, except that I altered the CdA to .24.

iBike_08_19_2017_1017_14_Miles.ibr

(207.11 KiB) Downloaded 283 times

iBike_08_18_2017_1008_3_Miles_CalRide.ibr

(60.46 KiB) Downloaded 277 times

IMG_0002.jpg (108.3 KiB) Viewed 5032 times

[Velocomp]

The temperature settings for your unit may be "off". Please contact technicalsupport@velocomp.com for next steps