Not registering power

[tess360]

I've had my iBike for about 2 weeks. And suddenly yesterday during the last half of my ride, the power meter stopped registering power. I figured it was that the log was almost full or something. I downloaded and erased all the rides and went out this morning and got almost no readings for over an hour.

Admittedly, it was a very easy recovery ride and I didn't care about the power readings. However, I'm concerned about how it's behaving.

Attached is my file.

Tess

[iodaniell]

The average of your slope data is -2, which would be ok if your route was downhill, but I suspect your tilt needs to be reset and verified.

Don't forget to reset your Wind Offset, too. It looks like that you *may* have started with a slightly negative offset.

[racerfern]

There is no profile attached to the ride. After doing your coastdowns and 4 mile out and back did you take the analyzed data and send the profile back to the iBike?

I tried pulling the profile info from the ride file and got the following:

Found 1 unique profiles for 1 ride files (0 ignored).
----------------------------
Gathered from 1 ride file
5/27/2008 to 5/27/2008
aero = 0.674
fric = 2.553
wind scaling = 4.541
CdA = 0.148 m^2
coastdown tilt err = 0.102%
Crr = 0.0045
A positive tilt error is almost unheard of. Also the fric number is very low IMO.

Take a look at the post ride analysis because of the tilt. Do these numbers make somewhat better sense?

[coachboyd]

Wow. . the wind scaling is WAY off in that profile. It should be right around 1.0
Because of that, your CDA is way low .14 would be the cda of a 60 pound woman with no arms and legs (ok, maybe exaggerated a bit)
I would redo the coastdowns and 4 mile ride. Wind scaling should be much closer to 1.0 and riding tilt should be a negative number (up to -1% I have heard) I have set at around -.4 and my green line in the graph above is almost always a straight horizontal line.

[iodaniell]

Wow. . the wind scaling is WAY off in that profile. It should be right around 1.0

+1

I think I read somewhere on this forum that with [some of?] the iBike Pro, you -may- have to manually set the scaling factor to a value of 1 (or whatever the default factory setting is), by using the advanced profile editor in iBike2, before recalibrating (CDs / 4 mile ride). At least, that was my impression from what I thought I read.

Maybe Travis can comment on this (again).

[travispape]

Isaias (iodaniell) had it right with his first post. The tilt is off and the iBike thinks you are riding down a 2.5% slope and is scratching its head wondering why you aren't riding any faster than you are. Of course, the answer is because you are not riding downhill.

It might be that you had a problem doing you tilt cal, or the mount may have shifted a significant amount rolling nose-down.

Regarding the Gather Profiles function that Fernando tried to use, that function is intended to be used on a large set of valid ride files. I created it for people who had used the old iBike1 program for months and wanted to go back to analyze their old ride files. (iBike1 did not have any analyze functions.) What that Gather Profiles function does is come up with a reasonable estimation of the profile parameters based on the data itself, so it doesn't make sense to use it for a single ride--especially one where the riding tilt was off so much in that ride. It was only a best-effort function for going back and looking at data acquired before the days of riding tilt and the windscaling factor and has been replaced with the calibration ride function.

So to the original poster, the thing to do is to check your mount to see if it got knocked nose-down and to get a good tilt calibration. Once that is working, go out and do your calibration rides to get a good profile so that any future problems with tilt can be later corrected by using the "Analyze Tilt and Power..." function.

Travis

[tess360]

You guys are all amazing and I feel well loved by all the responses. This morning, I put in a new battery, redid the tilt and wind calibration, and then redid the coast downs and 4 mile ride. Power seems to be working well today. My main concern is that for some reason my earlier profile disappeared. I put a post a couple days ago which no one has commented on about having lost the profiles. I have a Mac. I've just performed the upgrade that is supposed to correct missing profiles so here's hoping this doesn't happen again. However, I'm very nervous about deleting the ride data.

Yes, I've sent the iBike profile info back to the bike. I've analyzed a few previous rides and attached the new profile. Before I clear the ride data, how else can I ensure this doesn't get lost?

[iodaniell]

Before I clear the ride data, how else can I ensure this doesn't get lost?

Are you referring strictly to ride data or the coast-downs and 4-mile ride? The latter would be saved as a profile on your PC (Mac or Windows), and then, the profile is loaded into the iBike. Ones gathered from old rides on your PC are not needed. Clearing the data from rides should not clear the profile from the device or from your PC.

You can create multiple profiles each appling to a particular set of circumstances (i.e., a profile for when you are wearing winter clothing and your bike has fenders and bags hanging off of it, a profile for a stripped down bike that uses 700c x 25 high kevlar tires and non-aero wheels as opposed to your main profile that uses 700c x 23 supple race tires and aero wheels, etc.) I'm lazy about this, so currently, I use a single profile for everything, because I'm not worried about total accuracy for my commutes to and from work or even a 7 hour randonnuer ride in the mountains. I go after higher accuracy when training for races, only.

Each profile can be exported to another folder on your computer for archive purposes. The resulting file should have all of the right data in it to restore a profile if for some reason it disappears from the iBike2 software. All you would need to do is Import it back into iBike2, check it to see if everything looks reasonable, and then send it to your iBike.

Restoring a profile does not relieve one from having to check Wind Offset and tilt before a ride, however.