PT avg. speed not accurate

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I have a PT SL and I've been noticing the average speed on the display is off. Today, I rode three hours and turned a little over 55 miles, an 18-mph-plus average. My display read 16.9 mph at the end of the ride.

However, when I download my file, I get the accurate average speed. Any ideas as to what could be the problem?

--Dean

The difference is likely explained by differences in how your PTU CPU and your PC application are handling zeros. The CPU has a setup function to define this (Setup 3). I don't know about your PC software. Of course, if you were moving the entire duration, this isn't the explanation. But, a typical 3-hr ride has multiple stops when speed is zero (e.g., at least 5mins?).

It could also be a problem involving the interval function of the unit (inadvertantly switching the unit into, or out of, interval mode). When you saw 16.9mph, did you also view the distance as 55mi and the time as 3hr?

Thanks for the replies.

1) Yes, I did stop completely twice and the computer did go into sleep mode. (once for a flat and the other to get more liquid.) In setup, I noticed I have it in the "yes 0's'' function.

2) I did use the interval mode for 2x20-minute sweet spot intervals. Avg. speed is right. It's also right on my last 30 endurance miles.

So, is my setup wrong? Should I switch to "no 0's''?

--Dean

1) Yes, I did stop completely twice and the computer did go into sleep mode. (once for a flat and the other to get more liquid.) In setup, I noticed I have it in the "yes 0's'' function.

2) I did use the interval mode for 2x20-minute sweet spot intervals. Avg. speed is right. It's also right on my last 30 endurance miles.

So, is my setup wrong? Should I switch to "no 0's''?Yes, if you want to exclude stops from the avg speed computation.

Aren't there 2 setup options: 1) include zeroes while cadence is zero, and 2) include zeroes when speed is zero? I think I'm yes on #1, and no on #2.

The strange thing, is that if the difference is explained by not including zeros in the avg calculation displayed, it should result into the recorded data to be lowered than the displayed data, not the opposite.

I rode three hours and turned a little over 55 miles, an 18-mph-plus average. My display read 16.9 mph at the end of the ride.
So this here is very unlikely explainable by the 0s setting.

Thanks for the advice. I changed my speed setting to "no to 0's'' and now I'm getting correct average speeds, even when I stop during rides.

Just curious: Why would you want to have it average 0's in? Don't you always want to see what your average moving speed is? I also changed my watts and cadence to no to 0's.

--Dean

I also changed my watts and cadence to no to 0's.This will overstate your power and cadence numbers. The speed issue is different from power and cadence. For speed, zero means you're stopped. But, for watts and cadence, zero doesn't mean you're stopped.

This will overstate your power and cadence numbers. The speed issue is different from power and cadence. For speed, zero means you're stopped. But, for watts and cadence, zero doesn't mean you're stopped.
That makes sense. I think I'll change the watts and cadence back to yes 0. Thanks.