mschwett 

can anyone here who has a 4iiii dual sided confirm what the "correct" behavior is when paired to a head unit, smart trainer, iOS/android app, etc? in the 4iiii app (which looks nothing like the screens in the manual, thx guys!) my left and right sensors appear on a single line, "paired" to each other. but to all bluetooth hosts, i still see two, a left and a right.

i can connect to it, and i get a believable power reading and a balance value, but it would be nice to be sure that it's not doing something wacky like doubling the power of one side but also sending the actual balance.

this came about because i was trying to troubleshoot unreasonably low power values and discovered the two halves weren't linked. i was getting the left power doubled - i think - which i verified by some hand crank turning and a reconfig in the 4iiii app.

there are quite a few posts in various places about issues with these meters, but none that actually describe what the pairing looks like when it's WORKING!

FWIW, it's a factory install on a dura ace 9200 crank, which should hopefully not have the issues that the assymetrical 9100 cranks did.

OshkoshBiker

I have a 4iiii precision 105 Dual Sided Power Meter and I see two separate power meters when connecting to Bluetooth. As far as I can tell it appears they send data back to the head unit or smart phone independently as each side gives me about the same power. In the Bluetooth standard, there is a field to tell the app if it is a Left or Right PM. There are also manufacturer fields, which only apply to specific brands and no one has shared those fields with me, so who knows what data they contain. I don't know for sure, and maybe someone can elaborate on this, but it seems like any power calculation related to both sides is in the head unit or smartphone app.

Chuck
Cykelstrom.com

mschwett 

i did get some feedback back from 4iiii; they said to connect to the left meter, and as long as they're "paired" in the 4iiii app, the left meter transmits the total power. i didn't see any way in any cycling app to pair to both halves and have it combine the results internally, which isn't the way it's designed to work anyway, it sounds like.

OshkoshBiker

Thank you for contacting 4iiii and finding out. That is most helpful.

Chuck
Cykelstrom.com

mschwett 

here's what they said -

this is what i thought it was supposed to do, but it's very dumb that they still transmit both "L" and "R" for pairing!

OshkoshBiker

Agreed, it can be confusing.

Chuck