"The 33"-Road Bike Racing - Powertap setup (recording rate, display rate, ect...)

There seemed to be a lot of topics going on in the "Just started training with Power? Post your questions/comments here!" thread and I didn't want to take away from the advice other were getting so i made a new thread.

Anyway I just got my Powertap Pro+. I am just wondering what settings you have yours on and if I should switch anything up.

For Example:

Setup 1: Recording Rate. 1 second (12 hours) or 2 sec (24 hours). I would assume 1 sec is best? ( I have it at 1 sec)

Setup 2: Display Rates. 1, 2, 3, 5, 10, 30 seconds for watts, speed, and cadence. I have them all set to 2 seconds. Should I look into changing it to 1 sec, 3 sec, or 5 sec? Is it too jumpy at 2 seconds?

Setup 3: Zero's. I have it including zeros for watts, speed and cadence. Any reason to not include zero's? I also have auto zero on.

Setup 4: Misc. Sleep time. How many minutes? Default is 4 minutes. If i stop for whatever reason for four minutes and it shuts down, i will need to re wake it up? hit a button on the head unit and then spin the wheel and wait for it to refind the sensors before i can continue?

Cadence. Default is check pedal and then hub. The pedal sensor is extra. Is it worth picking up or is the hub accurate?

lactic threshhold. What the hell is this for? It has hi and lo. i have it at 0250 for both.

Setup 5: Learn functions. I used learn 1 to learn the hub for watts and the hrm. The computer gets speed from angular velocity from the hub and the circumference of the tire you input correct? The speed sensor is sold seperately? Why would you want the speed sensor then if the hub can calculate speed? And the cadence sensor is sold seperately? by default the hub calculates cadence based off of oscillations in power? Is that accurate?

and last, i thought i read somewhere that the cadence and speed sensor are the same unit and you choose which you want to measure with a switch on it. Is that true? Worth picking it up for either the speed or cadence?

Sorry this is long and thanks in advance for any input.

Setup 1, 2, 3, and 4 are all personal preference.

For the recording rate, 1 second could be considered "best" because you capture the most data, but it does limit the amount of data you can store.

Personally I found that 3 seconds is the sweet spot for the display rate. Not too jumpy, not too slow.

To wake up from sleep mode, just hit a button on the head unit and spin the wheel and you're good to go. Finding the sensor usually only takes about 5 seconds. If you find that it goes to sleep too often, increase the sleep time.

I've found the speed from the hub to be very accurate. Verified against a few other cyclocomputers. No need to get the extra sensor.

The cadence I have found to be slightly less accurate. From what I understand it calculates this based on oscillations like you said. I think it assumes there are going to be 2 power "spikes" per revolution (right foot downstroke and left foot downstroke) then calculates cadence based on that. Not sure if that's entirely true.

Seems to be accurate for higher RPMs above 80. Less than that, and it seems to get jumpy and inconsistent. Even at higher RPMs it's somewhat jumpy at times. Not really that big of a deal for me since I don't care that much about my cadence being 100% accurate. It's accurate enough for me to not worry about getting the separate sensor.

I use 1 second record, 3 second display refresh, include zeros, and default sleep (can't even remember what it is)

I don't have the cadence sensor for the PT, but I do use the garmin one when I use the 705. Cadence pulses from the hub seem adequate for my needs.