Problem with Powertap?

Alhana said:

While training I notice that the current watts display on the top row of my powertap goes to solid dashes and the elapsed time on the bottom stops, sometimes for 15-20 seconds at a time. I have never seen this before and it is kind of annoying having the display just feeze for that long. Have any of you with powertaps experienced this and is there a fix?

This means that the CPU is not receiving the signal from the hub. Some comments:

Non wireless PT: this usually means one of three things, (1) the hub batteries are weak and need replacing, (2) the sensor is not installed close enough to the hub or in the right position, or (3) some older (non sharkfin) sensors did this due to a vibration issue, usually while coasting downhill -- if this is the problem they will send you a new sharkfin sensor for free I think. There's also (4) possible RF interference from some near source of RF, but in my experience this is rare for the non-wireless version.

Wireless PT: (4) becomes cell phone tower/cordless phone/etc interference, and is more common for the wireless than wired PT. You can recognize this because it always drops out in the same locations on a ride.

lanierb said:

This means that the CPU is not receiving the signal from the hub. Some comments:

Non wireless PT: this usually means one of three things, (1) the hub batteries are weak and need replacing, (2) the sensor is not installed close enough to the hub or in the right position, or (3) some older (non sharkfin) sensors did this due to a vibration issue, usually while coasting downhill -- if this is the problem they will send you a new sharkfin sensor for free I think. There's also (4) possible RF interference from some near source of RF, but in my experience this is rare for the non-wireless version.

Wireless PT: (4) becomes cell phone tower/cordless phone/etc interference, and is more common for the wireless than wired PT. You can recognize this because it always drops out in the same locations on a ride.

Thank you for the tips. My powertap is the wired kind. You mentioned the hub batteries might need changing, is this doable for someone or is it best to send the hub back to saris? Can you even get batteries for the hub locally?

I think the computer also runs on batteries, should those be changed too? If so, I'm sure the computer batteries would be a cinch to switch.

Alhana said:

Thank you for the tips. My powertap is the wired kind. You mentioned the hub batteries might need changing, is this doable for someone or is it best to send the hub back to saris? Can you even get batteries for the hub locally?

I think the computer also runs on batteries, should those be changed too? If so, I'm sure the computer batteries would be a cinch to switch.

The batteries can be purchased locally, and changed yourself. Just remember to put some grease on the threads when you scrow the hub back together to keep it watertight. The owner's manual says for sure, but I think the computer batteries last at least twice as long as the hub, depending on the recording setting you have it on.

and search these forums for tips on removing the hub cover on the SL hub if you have an SL hub that is. It can be a bugger to get off first time.

I double checked the powertap and remembered it is the PT Pro model rather than the SL. I would guess the hub isn't too different, as far as taking it apart, from the SL model.

As for the grease, I figure something from the bike shop should do the trick. THe hub batteries are something like #457 or EPX76 Oxide type. An electronics store should have these.

Thanks for the tips guys.

If the battery holder on the pro is anything like the sl, be really gentle putting it back in the hub, and stop if you encounter much resistence. My sl has this flexible tab that sticks out of the hub, which the battery holder connects with when it slides in. The first time I changed the batteries, I guess it was not lined up just so, and I bent the tab a little.

Still, if you're not a klutz like me, it'll be fine.

What I have found, ( I have four wheels with PT's) change the bats every two months in summer, every month in winter, my riding is 600/800 a month (yours may vary), I have tired all different schedules to changing and found this to be the best.

I ride down to about 29/31 degrees F, after that It is too damn cold to ride, PT's have some issues at that temp, the better the bats the better the data as for less drops.

Tim Lamkin said:

What I have found, ( I have four wheels with PT's) change the bats every two months in summer, every month in winter, my riding is 600/800 a month (yours may vary), I have tired all different schedules to changing and found this to be the best.

I ride down to about 29/31 degrees F, after that It is too damn cold to ride, PT's have some issues at that temp, the better the bats the better the data as for less drops.

Tim, I have to ask...you said 'my riding is 600/800 a month', you don't mean hours do you??? If you do then I might as well quit the sport for being a slacker :o

Yeah, riding at temps much lower than 25-30 is a darn exercise in torture. Well for me at least.

Something kind of unexpected I found was I noticed a prominent drop in what seemed like a similar location. Sure enough, I went around the corner a half block or so and realized there is an array of towers of some sort there, maybe radio, maybe something else.

Regardless, I will check out some batteries locally, maybe radio shack can hook me up.

Me too. My PT Pro computer has now gone to heck.

Why me, Lord?! Not now! Big race Nove 11. I was mid come - back after a broken clavicle (Ti plate and 10 screws). Everyone wrote me off for the season. I was getting strong the scientific way. Now I may have to train with a HR monitor, argggggh...

Seriously, I went to zero out the torque and got numbers then dashes. I adjusted the wired shark fin and briefly got numbers again, then dashes. I have two hubs and 3 harnesses. Tried em all. Dashes. All the batteries have been changed. Dashes. Saris said $ 200 for a new one. No help.

Has anyone heard of the CPU's just dying? Anyone ever bring one back from the dead by installing updated firmware? Any suggestions?

i change my hub batteries about twice a year -- this is for the new Pro units (that look like an SL), the SL and the 2.4. I ride about 550 - 600 hrs/year.

I think i've needed to change my computer battery once so far this year.

The batteries in the old style Pro hubs last pretty much forever! mine were still working fine one unit that was 3 y old, at which point i just changed them anyway!

In answer to the dashes issue. Check the receiver unit is the correct one and correctly placed, and check that the cones on the axles are tightened correctly.

Lastly, if you or anyone has the *old* style Pro hub, please remember the allen key bolts should only be turned 7 times when placing the hub cover back on, else you'll likely break the hub.

ric

ric_stern/RST said:

Lastly, if you or anyone has the *old* style Pro hub, please remember the allen key bolts should only be turned 7 times when placing the hub cover back on, else you'll likely break the hub.

ric

OK tell me more my friend

Tim Lamkin said:

OK tell me more my friend

Turning the allen key bolts more than seven turns can crack the PCB circuit board and ruin your hub. (i think it's the circuit board, anyway, you'll ruin the hub)

ric

Cool...tanks

Alhana said:

While training I notice that the current watts display on the top row of my powertap goes to solid dashes and the elapsed time on the bottom stops, sometimes for 15-20 seconds at a time. I have never seen this before and it is kind of annoying having the display just feeze for that long. Have any of you with powertaps experienced this and is there a fix?

I once had a problem similar to what you described and found that my batteries were still good but they were loose. I had to take out the little battery holder, take out the batteries and then bend the metal clips inwards to make them hold the batteries tighter. That fixed the problem without changing the batteries, harness or position of the sharks fin.

Another point is that if you do replace the batteries it's best to use silver oxide batteries - they last a much longer time than alkaline batteries.
JB.

Well, prior to my PT cpu going bad, it had been acting bizarre, as if it was in serious need of torque zeroing. While doing that procedure the signal became intermittent and then gone. I called Saris and all they said was $200 for a new one. I asked if they would fix it and they said no. (what happened to the great customer support I used to hear about? Remember when the HR signal dissappeared, they would send out a new head immediately- no questions asked?)
Anyway, I tried to install new firmware (2.1 for my PT Pro non coded) but kept crashing, probably due to my aftermarket serial to usb cable. I'll be getting a proper cable this week and attempting it again. My hope is that the old firmware just somehow became corrupted. When that happens with the iPod you just reinstall and all is well. I'm hoping that will be the case here.

Has anyone had any experience similar? When I asked Saris if that would work, the guy just said, "you could try that..."

Chipotle said:

Has anyone had any experience similar? When I asked Saris if that would work, the guy just said, "you could try that..."

I brought my SL computer back to life by flashing it once. It had gotten stuck in "host" mode. After pulling the battery, it got stuck in "app ldr" mode, which was resolved by the flash.

Worth a shot...

How do you flash it?

Yes, pray tell. How do you flash it?

Chipotle said:

Yes, pray tell. How do you flash it?

Not sure if you can get there without registering (free), but this is the link to up to date firmware, instructions, and utilities:

saris.comt firmware.aspxOpen ↗

Edit: When I say "flash", I mean firmware update, which it looks as if you already know how to do / may have done. Different term - same thing😄