5X and Kickr - distance way off

Manual input of wheel size?

Wheel size was set for "automatic"...actually didn't think wheel size mattered on the kickr since back wheel is removed when connected to trainer. I will try setting to 700mm and test.
Thanks...

still not working

So I am a bit confused regarding trainers and Fenix. Tried another ride with F5X connected to Kickr Power and a cadence sensor. Set wheel size to 700 (but I don't think its necessary). Still get very low speeds and distances (compared to Zwift also connected to Kickr trainer).

When I initially connected Kickr to watch as a sensor, two different device ID's came up.

PWR - with id number (which I renamed PWR Kickr)
PWR - Wahoo Kickr AA4

I could then only get the watch to maintain connection to the PWR Kickr listing, and could never reconnect to the "PWR Wahoo Kickr AA4" sensor (it shows up as a known sensor in my watch settings, but won't connect).

My guess is the AA4 represents the smart trainer, while the other is PWR only.

Any thoughts? Is the Fenix just not compatible with smart trainers? Seems odd that I am still able to get some speed/distance detected, but only about 1/5 of the real total.

By default the Kickr's speed sensor reports the 'wheel' speed (ie the rpm of the large rotor the cassette is attached to on the trainer), and in simulation or standard mode this is useful but in ERG it is not. In the Ergometer mode, the trainer adjusts the brake to keep your power at the wattage the workout demands regardless of how fast it is spinning - you can be riding at a target of 190w at 110rpm in 52x11 or 60rpm in 34x28 and your power would be the same, but the speed and distance would be *very* different (as the trainer speed is dependant on the gearing and cadence, not the power). That is, if you create a workout with a 20w power target then put it in your highest gear you'll get an average speed of 40mph. Switch to 400w and go to your lowest gear and you'll average 10mph. Neither is an indication of how hard you are working as if you speed up/slow down the trainer's computer will detect that and compensate.

Some software applies a 'virtual' speed number that ignores the speed reported by the trainer and instead takes the power and then works backward to a speed using a physics model (ie at X watts an average rider on a flat road with no wind would travel at Y mph). Not sure if Zwift does that or not, but given your description that sounds a lot like what is happening. If it is the case, the Fenix is recording what the Kickr is reporting it while Zwift is calculating it's own speed from the power data.

If you have Wahoo's smartphone/tablet app, there is a virtual speed setting that you can enable on your trainer that will use a physics model speed value rather than the trainer speed when in ERG mode. Once you turn that on, it will remain in force as long as the Kickr has power (ie as long as you don't unplug it) so you just need to fire the app up once, change the setting and then use Zwift or whatever you want to do the workouts. It may use a different formula than Zwift though, so you may still get different numbers but they'll be a lot closer.

Wow, thanks...you should work for Wahoo!

By default the Kickr's speed sensor reports the 'wheel' speed (ie the rpm of the large rotor the cassette is attached to on the trainer), and in simulation or standard mode this is useful but in ERG it is not. In the Ergometer mode, the trainer adjusts the brake to keep your power at the wattage the workout demands regardless of how fast it is spinning - you can be riding at a target of 190w at 110rpm in 52x11 or 60rpm in 34x28 and your power would be the same, but the speed and distance would be *very* different (as the trainer speed is dependant on the gearing and cadence, not the power). .....

Very helpful! I will try your suggestions. The workouts I have done with watch connected were all in the "Erg" mode, so that likely explains the wonky distance/speed recordings.

BTW, the NOT useful response I received from wahoo support was "The KICKR is compatible with most devices that will connect to a power meter. With that being said, you might need to contact Garmin to see if that watch is compatible with smart trainers." Sounds like you understand there technology better then wahoo customer support.

Thanks again!