2.4 PT Dropouts

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Well after my commute today, it appears that the dropouts do occur at traffic lights.
As I hope you can see from the plot, as the speed drops as I approach a stop light the data drops and after I leave the data reappears.
http://img214.imageshack.us/img214/2426/plotcu0.th.jpg (http://img214.imageshack.us/my.php?image=plotcu0.jpg)

Well after my commute today, it appears that the dropouts do occur at traffic lights.
As I hope you can see from the plot, as the speed drops as I approach a stop light the data drops and after I leave the data reappears.
http://img214.imageshack.us/img214/2426/plotcu0.th.jpg (http://img214.imageshack.us/my.php?image=plotcu0.jpg)


Are they data drops or do you just get nothing because you're stationary? In other words what happens if you cycle past a traffic light that is on green? Does the speed and power stay correct or does it disappear?

ric

Are they data drops or do you just get nothing because you're stationary? In other words what happens if you cycle past a traffic light that is on green? Does the speed and power stay correct or does it disappear?

ricThat's exactly what it looks like to me. Time doesn't stop for traffic lights! The rest of the long zero power sections look like coasting down some decent hills.

on second look, there appears to be one actual dropout at about 26 and a bit minutes - power disappears, speed drops to zero and then restarts (along with power) where they left off.

Ric

That's exactly what it looks like to me. Time doesn't stop for traffic lights! The rest of the long zero power sections look like coasting down some decent hills.
I am using a 2.4 SL and when I first looked at the files, for a second I thought that the hub was dropping the signal again. But, then I realized what Alex says above, these are not drops but the clock moving when I am waiting at the light.

I now have about 15 hours on my rebuilt 2.4 and I have not noticed a single drop when moving.:)

Finally, another cyclist who doesn't regard red lights as optional stops !

Looking at the raw data, time continues but speed and power are blank.
It has to be a data drop, the transmission indicator goes off as well.
As this seems to only occur at traffic lights, when I'm stationary, I am happy to ignore this 'problem'.
Will email Saris and ask for their take on the issue.
The 26 minute drop, I'm sure I was going passed a speed trap radar!

Looking at the raw data, time continues but speed and power are blank.
It has to be a data drop, the transmission indicator goes off as well.
As this seems to only occur at traffic lights, when I'm stationary, I am happy to ignore this 'problem'.
Will email Saris and ask for their take on the issue.
The 26 minute drop, I'm sure I was going passed a speed trap radar!
The PT cpu quits recording when the speed (or HR; selectable) goes to zero. That's the way it works. - TF

The PT cpu quits recording when the speed (or HR; selectable) goes to zero. That's the way it works. - TFLet me modify that, if speed or HR are zero for 9 seconds. At least that is the way it is suposed to work and what I have observed except for the following.

On some steep walking Uphill sections while MTBing, the CPU will stop recording anything less than sabout 2 miles per hour. At least on the wired version. Doubt this will change on the wireless, but do not have one for my MTB.

Let me modify that, if speed or HR are zero for 9 seconds. At least that is the way it is suposed to work and what I have observed except for the following.

On some steep walking Uphill sections while MTBing, the CPU will stop recording anything less than sabout 2 miles per hour. At least on the wired version. Doubt this will change on the wireless, but do not have one for my MTB.The manual says:



If set on speed, "Trip time stops 3 sec. after if speed is not registered."



If set on HR: "...as long as a heart rate signal is registered."



TF

The manual says:



If set on speed, "Trip time stops 3 sec. after if speed is not registered."



If set on HR: "...as long as a heart rate signal is registered."



TFIs the number of seconds settable?

Cause I watch the timer count for 9 seconds before stopping after stopping the wheel. AFAIK it is not settable. Of course this is when set to Data (Watts) not Speed.

I actually never set it to HR or Speed instead of Data, so I would default to the manual. Don't use the HR strap much http://www.cyclingforums.com/images/icons/icon12.gif

I have found the manual lacking in other areas.http://www.cyclingforums.com/images/icons/icon9.gif

So when the transmission icon goes off that means what? The cpu is refusing the connection from the hub?
The recording stops when I'm still doing 7km/h, I suppose that I could stop before the next recording interval, 1.2 sec recording.

The other thing that crossed my mind is, do all PT graphs look like this?

Is the number of seconds settable?

Cause I watch the timer count for 9 seconds before stopping after stopping the wheel. AFAIK it is not settable. Of course this is when set to Data (Watts) not Speed.

I actually never set it to HR or Speed instead of Data, so I would default to the manual. Don't use the HR strap much http://www.cyclingforums.com/images/icons/icon12.gif

I have found the manual lacking in other areas.http://www.cyclingforums.com/images/icons/icon9.gif
I don't have a 2.4 to check, but on a Pro and in the 2.4 manual, 'data' is where you set it to either speed or HR - the only two choices. The number of seconds is not settable.

Agree that most manuals, Saris included, appear to have never even been read prior to printing. There are many mistakes and wording that looks like it has been translated from a foreign language. (WI isn't that foreign.) I bet they could cut their returns by 20% and their customer inquiries by 80% if they would just spend more time on their manuals.

TF

The other thing that crossed my mind is, do all PT graphs look like this?
Yes, it looks like a typical graph on a good day. I would say you had actual problems with the PT at 19, 26+, 38+ and 1:00+. Of course, that assumes that you were actually going downhill in all those places were you have speed and no power readings. - TF

I don't have a 2.4 to check, but on a Pro and in the 2.4 manual, 'data' is where you set it to either speed or HR - the only two choices. The number of seconds is not settable.Maybe when using speed only, like when not using a PT wheel(when not working), it auto stops in 3 seconds.

I just did an inane test. 2.4 with 5 sec speed averaging ticked away for 16 seconds, but only 6 seconds with 1 second averaging.

SL was 6-7 seconds irregardless of display averaging.

Both were set to record power. Tested with rear wheel off the ground and brought up to speed for 10 seconds and stopped.

On the SL I tested speed only by putting on a magnet and turning off Watts.
Spun wheel for 10 seconds and stopped it. Timer clicked by for 6-7 seconds.

I do not have a speed sensor for the 2.4. So I can't say.

I repeated all the tests a few times for consistency.


(WI isn't that foreign.)
TFhttp://www.cyclingforums.com/images/icons/icon12.gif

Long ride in the country today and plenty of drops, well 11 in 4 hours.
I feel inclined to just ignore the drops as they are pretty much only for a second or two.
Is this a reasonable position to take?
And just to make you Northerners in your basements jealous, 25c and sunny.

And just to make you Northerners in your basements jealous, 25c and sunny.


DesFLurane, I couldn't take it anymore ... 8 weeks of Spinervals in the attic is driving me nuts to get back on my bike:

http://cgim.audiogon.com/i/vs/s/f/1169992272.jpg


SO, today for the first time in 15 years, I have managed to ride my old road bike on March 1 OUTSIDE !!!! It was a balmy 1C (-4C windchill) this afternoon when I escaped the hospital to get a real ride (instead of doing the Spinerval Hillacious DVD). I'm impressed, this is the first winter I have taken my trainer sessions more serious with 4 per week x 8 weeks, and it showed on my first 25 mile ride with 1500 feet of hills this afternoon. Unfortunately, a huge storm is hitting tomorrow with snow, rain, and heavy winds. Back to Spinervals this weekend I guess ( my old Trek is back on the trainer)... I have to get ready for my upcoming trip to the bay area, California in May.

Meanwhile, your experience with the new hub is still making me drag my feet on buying my own. Given I don't race and this is for fun only, I may start with the Polar CS600 Power on my new bike and test my aggravation level with that thing ... before taking the big plunge.

Just take the plunge, it looks like the cpu memory is really small on the new polar, like 4 hours at 1sec recording, just not enough for any reasonable road workout/ride.

Buy the PT, you know you want too.
I could not imagine riding my bike without one. I'm now scheming how to buy a second PT and put it into an aero carbon wheel :cool:

Nice trainer setup BTW:)
Do you have a sub with that system as well?

Nice trainer setup BTW:)
Do you have a sub with that system as well?

Thanks.

About 5 weeks ago, my wife moved me from our 3rd floor office (above our bedroom), to my sound-isolated audio room on the 3rd floor after my 6.30 am trainer ride woke her up. She thought there was a snow plow outside, until she realized I was riding the trainer above her. The advantage to being in the audio room is I can listen to music through my speakers, rather than an iPod, and not wake anyone up. As well, I can project Spinervals or Tacx DVDs up on the big screen. But to be honest, I really can't concentrate on intervals and appreciate the music at the same time. The music is there for background and to limit boredom. I think next winter I will spring for a Tacx Fortius and park it the room.

I have no sub in the system, just the 2 full range Kharma's (Grand Ceramique Midi's). But, given the Kharma type of bass, I have toyed with buying a matching sub, but I opted for a Cervelo R3 instead.