PharmD

My Garmin HRM strap has been weird lately. It reads normally for the first few miles of every ride, but then it jumps up to 243 bpm and gets stuck there. I've tried cleaning it, replacing the battery, and using electrode gel. It happens outside and when I ride on the trainer. It's not the head unit either because it happens on Zwift with the USB ANT stick too. Is it time to replace it or is there something else I can do? It has been reliable for the last 3 years up until now.

Ravenwing

Have you tried a different strap? That'd be my first instinct after what you've already tried.

John_V 

I had the same issue with my old Garmin HRM. I ended up giving the electrode portion of the head unit a really good cleaning with some soap and a toothbrush to get in between each of those ridges. Salts from your body will deposit in those ridges and can block the conductivity between your skin and the electrodes. This worked for me but if after trying everything you have done and this doesn't solve your problem, a new HRM may be your next step.

MattFoley

I also think the issue is likely the strap...both of my Garmin straps seem to be reaching the end of their life (a couple of years) and have gotten a little wonky lately (getting stuck at some random BPM number, then dropping out for a bit) despite fresh batteries. From everything I've read, it's pretty common for the straps to just quit working after a while (maybe corrosion? or maybe the internal connections have a flex limit). I started using a Scosche Rhythm as an alternative and really love it...particularly since I can put it on after my kit is on, so I don't have to undress if I forget like a chest strap requires.

Cychologist

The Garmin strap is their weak link. I replaced mine with the Polar (strap only) and no more problems.

John_V 

The design of the Garmin HRM does seem to have issues in the way the electrodes are attached to the transmitter as a single unit. My old Sigma HRM is of the same design and I went through several of them before I started to use Ant+ sensors to connect to my cyclometer. At the time, Garmin was the best choice. I think the constant bending of the stiff electrodes eventually causes the circuit inside to break and thus give you the bad data. At least that is what was happening with my Sigma. I do like the newer designs, such as the Wahoo Tickr and Polar H7 HRMs, where the electrodes are on the strap and not part of the transmitter. Straps are much cheaper to replace than the complete unit. The advantage that the Tickr has over the H7 is that the Tickr is both Ant+ and BlueTooth whereas the H7 is Bluetooh only.

bassplyr

I switched over to a Scosche HRM earlier this year and love it. No chest strap and the flaky connections that go with it. I just put the snesor, about the size of a digital watch under the leg of my bike shorts and forget about it. May still get an occasional flaky reading, but much more comfortable and much more reliable.

Seattle Forrest

I can't confirm this personally but I've read that the Tickr family doesn't get HRV right over ANT+ although it's perfect over Bluetooth.

No optical sensor (Scosche, Mio, etc) gets HRV right ever.

PharmD

I have the Garmin classic strap...is the strap even replaceable on this model?

It's this one: https://buy.garmin.com/en-US/US/shop...prod10996.html

Seattle Forrest

No, it's not.

My classic strap (same one) died this summer after many years. New battery didn't do anything. Cleaning the thing very well didn't bring it back. Just konked out. I got my money's worth out of it. Replaced it with an HRM-RUN and also a Mio Fuse when I'm swimming.

John_V 

I don't know the answer to that but the reason I made the switch was because the Ant+ bridge in my Wahoo RFLKT+ started locking up with the Garmin sensors. No issues now that I went BlueTooth. The wrist type, optical sensor, HRMs seem to be overtaking the chest strap models because of their comfort level but I prefer the transthoracic electrodes over the optical sensors that work by detecting capillary refill. Plus they aren't as expensive.

Looigi

The woven elastic strap is replaceable, but the contacts, wiring and transmitter are all in the plastic part. Replace the elastic strap when the elastic gives out. I have one of these going on 5 years and except for some high readings in cold low humidity conditions, it's been fine.

RR3

I have gone thru two woven Garmin HRM straps this year alone. Cleaning helps but they die. The Polar strap is slightly better and only one failed so far.

I had one Garmin classic (all plastic encased) fail this year. Odd readings as OP noted....250 BPS and no way to reset. The classics seem more durable.

I do ride a lot and sometimes for days on end but then again perhaps I am just a salty old dog.

technobuyer

I have the Tickr and use it to broadcast Ant+ to my Garmin 800, and over BT to my polar M400 watch simultaneously. Comparing after a hard ride last night, the Max recorded in both cases was the same(166 bpm), and the avg bpm's were slightly off at 149/150. FWIW.

chong67

I have the Polar H7. I use it 8x and the battery is still at 100%