Assistance with Wahoo Kickr

I’m in the process of transitioning from street riding, to sunny indoor wahoo speed/cadence setup, to wahoo kickr, and I am unsure my setup is actually working correctly.

Outdoors riding I can do 20 mph easily on flat ground.
Sunny indoor I can do 20 mph easily.
Wahoo Kickr I’m struggling to maintain 15mph flat ground.

Outdoors if I am in my tallest front smallest rear full crankdown I am literally doing 45mph.
Sunny indoor since no resistance is measured I am capped at 100 rpms cadence.
Wahoo Kickr has me at 85 rpm doing 15mph flat ground in a pretty high gear ratio.

Up a 10% gradient 100% trainer difficulty I am hitting 500w and the rear flyweight is coming to a dead stop in seconds. I do a small coast and I am still averaging my 3 seconds so I am still moving. After a second of no pedaling I take another full crank kick to spike my watts and keep moving.

On flats if I coast for 3 seconds my rear flyweight is still spinning very fast, and I know outdoors on my bike I’d be coasting for awhile as it dips down slowly in mph. In the game 3 seconds of no pedalling, my rider pulls over since I am not putting out watts.

When I calibrate my Kickr it seems to actually know when I am pedalling 25mph and how long it takes to coast down to 13-15mph but in Zwift all the real world stats seem to get tossed and everything just goes off watts and cadence.

Is my Kickr operating Zwift correctly or is their a setup/setting I have been overlooking? Is Zwift completely against 3 second coasting?

Update: I never updated the software. I linked it to Zwift directly I guess I figured it would update automatically. I am now linking it to wahoo fitness app, and discovered my wheel size was inaccurate. Idk how much a difference these things will make, but I’ll keep you guys posted.

Three seconds of coasting should be fine if you’re doing a decent speed.

Double-check that you’ve entered your weight correctly into Zwift. If you’ve accidentally set it way too high then that could explain what you’re seeing.

na i am proud of my 25lbs lost in a week. I am accurately weighed into the game at 186lb.

i can be 25mph and try to enter a coast and within 3 seconds my rider is pulled over. when I am in the calibration it takes my bike 15 seconds to coast down from 25mph to 15mph which is fairly accurate outdoors.

Well yes and no. Zwift is not like real world riding but if you stop pedaling on a descent you will coast a bit more even at 0 watts and if the decline is over 3% and your speed is 35mph or above you will actually aerotuck and gain speed even at 0 watts. Cadence really only affects speed by the way it contributes to watts which does affect speed.

What kind of coasting can you perform on flat ground? can you coast from 25mph to 13mph or do you get pulled over within 3 seconds like i do?

On a 0% grade my avatar will come to a stop pretty quickly. I have observed that sometimes it appears almost instant and other times it can take some seconds but nothing compares to what it’s like in real life.

Thanks for letting me know. I guess it’s just how the game operates. Updating my kickr and launching through my fitness app made no difference.

Basically, unless downhill over 3% there is no coasting. Even when drafting the best I can get is a slight easing in the power but nothing like in real world. It’s an art to learn how and where you can find some relief when racing or trying to ride with a string group. I have found that direct drive trainers are better than wheel-on trainers which offered no relief at all. Again, these are just my observations and others may have different experiences.

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You mention 100% trainer difficulty. Zwift defaults to 50% and my guess is most people leave it there. Unless you are wanting maximal impact of the hills, I’d suggest taking that back to 50% and see if that makes a difference for you.

i tried all settings and i do want 100%. my trainer behaves the same on all settings. seems like calibration the speed is based off of the flywheel, but playing zwift the speed is based off of cadence and watt. To me it makes most sense to base speed off the flywheel.

can anyone else verify how their kickr behaves?

does your flywheel continue spinning after you have 0 watts and your character stops?

does your flywheel stop quickly up gradient after a high watt kick and your character still moves?

Do most people switch to instantaneous readings instead of 3 sec avg?

Do you turn off erg smoothing? is that strictly a feature used during erg?

really i cant understand how a person could ride at 500watts using this setup. it seems like im around 120watts currently and if i were to reach 300watts id be in my highest gear full blast. since the speed is not based off the flywheel it would be spinning too fast to be able to apply any more power to it on flat ground.

is their a way to add some resistance on flat ground so my flywheel isnt spinning out of control and i can raise my watts?

the main reason i am focused on coasting is my flywheel is spinning out of control on flats.

when i set my game up through the wahoo speed censor and the cadence censor i selected “speed” in the pairing then had to select the speed censor then had to go to unsupported smart trainer at the bottom of the list. when i plug my kickr in and pair it does it have multible options similarly? maybe i goofed in the pairing step? after work today im going to check into that as well as check into the wahoo fitness app numbers. i am suspecting the wahoo fitness app will give me significantly different readout numbers. Can anyone else check their wahoo fitness numbers compared to zwift and tell me if they are the same or if the game chops it all down?

I’m not sure if I’m quite following this correctly, but if you have a Wahoo Kickr then you don’t need to use the seperate speed and cadence sensors at all - The Kickr will send power, and cadence (if Kickr 18 or later) to Zwift and then Zwift will calculate the speed from the power and other variables such as height/weight/gradient etc.

In the pairing screen you should have the Kickr paired as a power source, controllable trainer and cadence.

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does it even give you the option to set it up as a speed source? im thinking since my old setup was as a speed source maybe it got goofed.

No, I don’t think so and it doesn’t need to. A speed source is only needed for ‘dumb’ trainers that aren’t able to send power data to Zwift. All Zwift needs is the power output - it calculates the speed from that


Do you pair as controllable and Power.

What bicycle do you on Zwift and what gear ratio?

In Zwift the Avatar come to a quick stop on flat road if you stop pedaling, that is normal.

doesnt make sense to me. if my flywheel is spinning and in the real world i would be moving and in the calibration i am still spinning down i should be moving in zwift.

You need to produce power to move the avatar, the spinning flywheel does not generate power.

Zwift calculate how quick your avatar stop when your power goes to 0 and it is the same for all riders.

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