My heart rate was all over the place with the garmin strap. I picked up a replacement polar wearlink strap and snapped the garmin transmitter into it and haven't had a problem since. I had huge concerns as it was my only metric besides pace for IMMT and the heartrate was totally unusable. The polar strap worked perfectly all day long in cold temps, warmer temps, wind, and a little rain. Sorry I can't help out with the other issue, never had that happen.

no help to be offered here, but my 910xt had an epic fail at IMMT it left itself at the condo was was not on my wrist at the start line.

carried by edge 800 with me to have a clock on the run and actually paced myself relatively well.

to paraphrase Rappstar's best piece of IM advice it is a long day even at the pointy end of the field and getting hung up on small details is a great way to blow the big ones.

---

"When the going gets weird, the weird turn pro."
Hunter S. Thompson

Get the old style Garmin strap, the new one sucks.

Can't help you with the turning off issue, have not had that problem with mine. My old 310 started to do that after a couple years and it was because the top was separating from the bottom slightingly and the batter terminals would lose contact with the battery. If the 910 isn't ruined from water though, I doubt that is the issue.

My watch acts weird (dropped signals, spikes, etc) when the memory is almost full. Try deleting some old files.

I know it sounds elementary, but did you try changing the battery? This won't help the 910 itself, but I find when my HR goes wacky it's the battery in the strap.

---

_________________________
I got nothing.

Thanks will try that.

Thanks...it was one of the first things I tried.

Use a standard Garmin HR strap (the one that comes with 305)

Don't use the quick release. Use the watch on the wrist and it won't shut off.

Same issue with the HRM started last weekend. Changed the battery, but no difference. I, too, am going to IMC in 4 days so I bought a new strap at REI today. Sure hope it works.... There must be some "weak link" in them; many people report that they die after 2-12 months. I had mine for about a year. My previous "standard" Garmin strap worked fine for years before it was stolen (but was slightly less comfortable).

My wife has the same issue .... with every strap. They last a few months and then boom, start acting erratically and then they give up entirely. They still work on me though.

As an aside. Most HR monitors will spike. Things like powerlines or flapping technical fabric next to the strap on a windy descent.

I am guessing a new strap may work. I don't think it is a watch issue.

Re watch shut off: Do you have a quick release kit attached?

---

https://www.pbandjcoaching.com
https://www.thisbigroadtrip.com