Setting Crank Length - Multiple Bikes and Multiple Devices

Hello,

Curious how crank length is being set. I have multiple bikes, multiple Garmin devices. The devices are all newer devices with the "sensor pool" functions (520, 820, Fenix 3, FR935)

My understanding was that crank length is stored in the pedals, It's only set when I manually adjust the settings then the device sends the pedals the updated crank length.

Example: So when I move the pedals I only set the new crank length (172.5) in the first device I use, say my 520. Assuming the length gets set then next device I use, say the 820, reads the length from the pedal rather than setting it to the value from last time it was used (170).

Is this a correct understanding? Or do I need to set it on each device?

0 Former Member over 7 years ago

If the head unit supports setting a crank length then it becomes the master and will change whatever crank length value is currently on the pedals to the value on the head unit that is talking to the pedals.

If the head unit does not support setting the crank length then the values on the pedals will remain unchanged.

So if you switch from using the 520 to the 820 then the 820 will configure the pedals based on the settings it has stored.
This will impact:

Crank length
TE/PS - whether this is on or off
Cycling Dynamics - On/Off
Auto-zero - On/Off

0 stevenknapp over 7 years ago

Excellent, thanks for the help!

I have noticed where I set the length, say to 170.0 and when I go back in settings it shows 172.5. Any idea why this is happening? I had thought it was reading it from the pedal.