If you've paired it previously for training, or at a different race - it should work fine with no problems - atleast that has been my case every time with both a 910 and a garmin 500.

I am not 100% sure, but I think I may know the answer.
On the 910's initial setup, it asks you if you have a power meter, HR, speed/cadence. If you say "yes", then the next time you turn on the watch, it'll look around and pair with whatever it can. It should then lock in those devices from then on, but I am not sure that it does.
Try redoing the initial setup and then say "No" to all those. Then go into settings and pair them manually. I think that will solve the problem. Hopefully, you can find a group ride to test this before your next race.

FWIW, that is exactly how I set up my 910 and 500, and have no problems at all booting it up in a sea of ANT+ devices.

Thanks - I'll try that. My concern is that I don't in fact have opportunity to test a solution before the race (this coming Sunday), so will have to hope for the best. Your workaround makes a certain intuitive sense to me, esp since it seems to have worked for you.

It's Tuesday. You won't be on your bike between now and raceday?

I will, but not surrounded by competing powertap hubs.

I've never had a problem with this. I paired my 910 and my Timex GT over a year ago to my PowerTaps and they just detect it when I turn the watch on. Worst case, take the rear wheel out of transition :)

---

Rodney
TrainingPeaks | Altra Running | RAD Roller
http://www.goinglong.ca

Are you borrowing/renting a wheel set? The pairing thing is a one and done deal. You shouldn't have to repair unless the battery on your PM/HRM/Speed/Cadence sensor dies--simply turning your 910 off and on should not reject the pair that should already be set up on a device you own. Worst case scenario you CAN set this stuff up on the fly. I have 2 HR straps and since you can only pair with one at a time I do occasionally end up at the starting point of group rides or races with the HR strap that is not paired. All you need to do is get yourself some space from the folks around you -- 20-25m will do it if there are a lot of ant± devices present--and initiate the search for whichever ant+ sensor you need to pair. It's about a 10 second deal--I have done it in the middle of a sprint Tri before.


TL;DR You shouldn't have to repair each time. Pair your shit ahead of time, pray that it works, and familiarize yourself with the steps so that you can do it mid-race if the prev. steps fail.

---

__________________________

I tweet!

Couple of questions because iam also a new owner of a PT and have a 910. So during races I use the auto multi-sport in that when i press lap it goes from swim to t1, press lap again it goes into bike, lap again to t2 and one final for run then end. In that scenario, i would think that pressing the lap that starts the bike leg is when the 910 would attempt to calibrate the pt. If that is true that usually happens when I mount the bike and much fewer bikes are around. I will simulate this and get back to you guys but if thats how it works i would expect less issues.

i know for the HR monitor you can pair it based on the code. So if you pair it once and figure out what that code is you can manually enter the code and it will stay set to that. I'm not sure if that works for the powermeter though. I did that on the HR monitors so it would stop doing that when my fiance and I turned both the units on.

I'm at a loss for figuring out what you all are doing that is causing your 910's to "forget" your sensors...

Something to do with the setup?

I always get the option to "recalibrate" my powertap whenever my watch first detects it, but I don't have to re-pair it.

---

__________________________

I tweet!

*this*

As the OP, I'm at a loss too, hence the post. I paired it as per the manual when I bought the (new G3) PT hub this spring, and it worked without a hitch until said race, which was likely the first time I switched the Garmin on while there were several other PMs in range. I'm going to try and restart and re-pair the unit manually before my race this weekend and hope that works. Not interested in digging through menus either during T1 or while out on the bike course. Thanks for a ll the replies!

FWIW, I got the "multiple power meters detected" message on the 910 when I powered it up before the race, before initiating the multisport mode, not during T1. So at least my unit attempts to pair as soon as powered up in Cycling mode apparently. In any case, I'd prefer not to count on being the last one out of the water in my wave to ensure an empty corral, even though that is often the case anyway ;-)

On your 910: Mode | Settings | Bike Settings | Bike 'x' | ANT+ Power | Sensor Details.

If the Sensor ID reads zero (0), then you are not paired with your specific power meter. Go back to ANT+ Power, enable your power meter by spinning the wheel or cranks, then select 'search' on the 910 and when the 910 finds it, back out of the menus and then power-cycle the 910. Go and check the Sensor Details again to see that it now reports your proper sensor ID.
When you initially enable a power meter on the 910, it will search for the power meter but it doesn't explicitly store the ID until you go through the above pairing process. Once you've done that it will find that power meter exclusively until you go back and select 'search' again. Do NOT select 'search' when you're in an area full of power meters because once you're in the 'multiple power meters found' state, it will not properly save the IDs.

---

Less is more.