Powertap Dropouts?

I’ve got an Edge 500 and a powertap SL+. When I have the garmin set to autopause- every now and then (a few times /hr) I see it chirps at me and says it’s paused… often when I’m cruising along at 20mph. (yeah- I know I’m not supposed to set it to autopause as it changes the power metrics… but depending on my specific ride, I like to time myself and have it automatically cut out the traffic lights)

Anyway- I get speed dropouts regardless of whether it’s on autopause or not, and I’ve had it with two different Garmin Edg 500’s.

So- I took a look at the TCX file and sure enough… yup- there are dropouts.

do all powertaps do this? is this indicative of something? Like- it’s on its last legs and about to go belly up, or my battery just needs replacing? Anyone else have this issue? What’s the deal here?

here’s an image of a portion of the TCX file with a dropout shown.

http://i45.tinypic.com/1zev7u1.jpg

I use the speed and cadence sensor from Garmin with my power taps.
I never have an issue. When I use just the power taps I was getting random drops in speed and other data. You might want to try that. Yo can also run two garmins or computers and see if the PT drops out then. I do run two edge 500

I’ve had it happen to me for a variety of reasons (wired PT) but the only one that may exist with a wireless system was related to a loose cassette. Still not sure why, but in the process of investigating why I was getting the drops, I noticed that my cassette had come a bit loose. Tightened it up, and they went away…

do all powertaps do this

I’ve got 1000+ power files from a lot of different users.

The overwhelming majority of files with dropouts are when paring a Garmin product with either a Quarq or PT.

Thanks for all of the replies.
I also posted this over on the Garmin forums, and got what I thought was a pretty good answer-.

Turns out, that sometimes these dropouts are correlated with the Edge500 searching for a sensor to pair with, that isn’t there. i.e. such as if you have two bikes, one with a speed/cadence sensor and not a power meter, and the other, vice versa (in my case). I did experience this- as once when a pack or cyclists when by (across the street, in the other direction), my Garmin chirped at me asking me if I wanted to pair to the Speed/Cadence sensor that it just found.

My bike profile was set up to be looking for a Speed/Cadence sensor that wasn’t there! Terrific - a solution. Now that I’ve adjusted my bike profiles so that it’s not looking for another ANT+ sensor to pair with, at least for the past two days which included 3-1/2 hrs of cycling, I didn’t notice a single instance where my Edge would autopause on me while moving. Yay!

I thought the problem was solved, but just for fun I checked the TCX files. oops- nope. There are still about 20 dropouts per hour. So now I don’t know again… but it seems to be much less of an issue now? not really sure.

I’ve had it happen to me for a variety of reasons (wired PT) but the only one that may exist with a wireless system was related to a loose cassette. Still not sure why, but in the process of investigating why I was getting the drops, I noticed that my cassette had come a bit loose. Tightened it up, and they went away…

Hmm. That’s an interesting thought. I’ll tighten up my cassette tonight and see. I do my own wrenching… and since I pretty well suck as a bike mechanic, I wouldn’t be surprised if my cassette was loose.