Negative crr

[m234232]

I am getting quite frustrated with my iBike. I have always used it on my road bike and have enjoyed it for over a year, but I am trying to use it on my TT bike and can not get an acceptable calibration. I ride a 2011 Specialized Transition Pro with rear disc tubular and front Zipp 303 tubular. I have an iBike Pro with the wind tube mounted mid and below my drop wing on the aero-bars (midway between the brake end of the drops and the arm rests of the bars). I have tried to calibrate 5 times and each and every time I get "crr out or range." In other words it is a negative crr. I have attached the raw data non-corrected or changed. I am conducting the cal ride as instructed and always do my coast downs slightly up hill. Someone please tell me what I am doing wrong.

[racerfern]

I think you've got some weird value stuck in the iBike profile and it won't go away. With Crr forced to .0041 try the attached profile and let me know how you make out. After installing this profile you might want to try another cal ride and coastdowns to see if we can get you dialed in closer.

[m234232]

Thanks. Will do.

[m234232]

Here is what I got today. I was finally able to get the Crr "acceptable." The next question is do I eliminate the coast down outliers from 5/7/2011 and 5/10/2011? I also discovered my wind tube fits quite loosely in the wind port. It does not take much to dislodge it. I wonder if a wrap or two of electrical tape around the port adapter may tighten it up? The attached file is after "Crr adjusted" on my computer. I am also attaching the the raw file too.