AeroPod, PowerPod and Newton

Mine reads -0.468.

Is this acceptable for proper performance?

Sounds about right. Mine was -0.461 and I just made an adjustment to -0.500. That is the amount of flex I cause by leaning on the bars.

racerfern wrote:Sounds about right. Mine was -0.461 and I just made an adjustment to -0.500. That is the amount of flex I cause by leaning on the bars.

I just set up my iBike and noticed the same thing. I did the tilt cal with me sitting on the bike and it came out to -.5 degrees (+1.0 and 0.0 with no weight).

Do you know if the iBike software can adjust this value in the iBike based on ride data, or is it only able to tweak the ride files after the fact? It sort of looks like the "Advanced Profiles" screen will let you tweak the tilt in the iBike, but I'm not sure. Seems kinda important... 0.5% grade isn't that tiny.

rruff wrote:

racerfern wrote:Sounds about right. Mine was -0.461 and I just made an adjustment to -0.500. That is the amount of flex I cause by leaning on the bars.

I just set up my iBike and noticed the same thing. I did the tilt cal with me sitting on the bike and it came out to -.5 degrees (+1.0 and 0.0 with no weight).

Do you know if the iBike software can adjust this value in the iBike based on ride data, or is it only able to tweak the ride files after the fact? It sort of looks like the "Advanced Profiles" screen will let you tweak the tilt in the iBike, but I'm not sure. Seems kinda important... 0.5% grade isn't that tiny.

There's no need to worry about a large value of riding tilt causing error in your power readings. The riding tilt is accounted for in the iBike FW by the fric calibration factor. The key is just be consistent with doing a good tilt cal before your rides and to use the same riding position. On the road, fric takes care of accounting for both the riding tilt and the rolling resistance. Later when you process the ride, iBike2 splits out the 2 phenomena and separately corrects the tilt and shows rolling resistance loss.

Also, I would recommend doing your tilt calibration off the bike in order to be as repeatable as you can about it.

Travis

Took my iBike out on it's maiden voyage today (coastdowns and 4-mile) and now I think I understand what you mean. During the 4-mile ride, the software figures out how much your weight on the bars effects the tilt. The amount of tilt directly effects the Crr determination also. For instance, because I did my tilt cal with weight on the bars (and it was too much) iBike2 determined that I had a +.3% offset to the tilt... most people will have around a -.5% offset if the do the tilt cal unladen. But anyway, after the coast-downs and 4mile, iBike2 gave me a Crr of .008 and along with the +.3% tilt... which is identical to a Crr of .005 and zero tilt... which is about what I'd expect. So if I understand correctly, you want to do the tilt cal with the bike unladen, then let iBike correct for how much your weight on the bars effects the tilt based on your 4mile results.

So what do people generally get for tilt and Crr? Seems like tilt of about -.5% and Crr ~0.000 would be the norm.