Wahoo Kickr Core 2 speed and distance
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I recently purchased the Wahoo Kickr Core 2 for indoor cycling cross training. When pairing my Race S with Wahoo, I see that the pairing supports “Power, Heart Rate” but not speed, although cadence gets recorded. However, when pairing the Wahoo with https://auuki.com, I get speed in addition to power and cadence.
Am I missing something to enable speed on my Race S, or is it not supported? Running firmware 2.50.28.
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@atoponce If I had to guess, then I’d say the app you are using is doing bluetooth FTMS (FiTness Machine Service) to get data while Suunto is using CPS (Cycling Power Service).
https://www.bluetooth.com/specifications/specs/fitness-machine-service-1-0/
https://www.bluetooth.com/specifications/specs/cycling-power-service-1-1/
If it helps, for indoor cycling “speed” is always fictional, as you are not moving from where you started so you’ve done no distance and no speed. Outdoors, speed can be affected by elevation changes more than effort, so one could do more effort moving 10kmh uphill (say at 300w) than moving quickly downhill at 50kmh at almost no effort (say 50w); therefore, power should always be used to represent your effort in both situations. You should still know speed outdoors to obey traffic laws though!
I connect my Stages SB20 power meter to a Race S and never get speed/distance, but I don’t desire to get those as power (watts) and energy (joules) covers what I need.
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@raven Thanks. I’ll dig into those specs and the Auuki source code. Seems reasonable.
As a counter point, when you’re running on a treadmill you’re not moving either, but still have a pace and distance based on your cadence and stride length. Elevation nuances also apply here, even though you can set an incline on the treadmill.
And yeah, the power and cadence (sometimes HR) is honestly the only thing I really care about. I was just curious why that metric was missing. I assumed it has something to do about tire dimensions and gear ratios, but remain confused when doing a virtual ride in Zwift and speed is present in the data.
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@atoponce said in Wahoo Kickr Core 2 speed and distance:
@raven Thanks. I’ll dig into those specs and the Auuki source code. Seems reasonable.
As a counter point, when you’re running on a treadmill you’re not moving either, but still have a pace and distance based on your cadence and stride length. Elevation nuances also apply here, even though you can set an incline on the treadmill.
And yeah, the power and cadence HR is honestly the only thing I really care about. I was just curious why that metric was missing. I assumed it has something to do about tire dimensions and gear ratios, but remain confused when doing a virtual ride in Zwift and speed is present in the data.
I dislike treadmills as their estimations often differ from my outdoor experience. I’ve been running for decades, and I typically do about 4:45/km for a zone 2 run, but indoors, if I do this by “feel” then look at the display, some treads give this as something like 3:30/km which is ridiculous (likely due to being hotel treads poorly calibrated). Treadmills can also use bluetooth FTMS to broadcast data, but I don’t think any watch uses it. Instead, it’s apps like Kinomap or running in Zwift that can use FTMS. Apple has their own GymKit protocol that can get “distance” and “elevation” but whether you trust that or not is up to you.
You can use a footpod to know how much your legs have actually moved but it’s still not the same as outdoors due to differing environments. With a Stryd footpod, I imagine you can get power data even indoors (?), which might be better than the estimated speed from a treadmill, even though running power is always estimated rather than measuring strain like on an actual cycling power meter.
For cycling, you could take your average cadence (rpm) and multiply by the tire diameter to get a similar “distance” criteria, but that’s going to suffer for reasons you might imagine. Pedaling doesn’t simply move the wheel and then stops but instead has momentum. Meanwhile, with running, you don’t have the same momentum to deal with.
Overall, on a treadmill, two things are moving: the tread belt and your legs. The treadmill isn’t measuring your legs. A footpod can measure your stride. That measurement is somewhat useful to compare with outdoor running but is imperfect. On a cycle, your legs pedal, but the bike itself creates a faster speed outdoors than your legs can do alone. When we measure speed, it’s how much the bike moved, not the person. Use cadence over time to figure out what the person’s legs did. Power data is certainly better than speed for cycling to measure your effort. For running, using power is still fairly new in comparison.
Come to think of it, I think for running indoors, if I can’t have an indoor track, then a manual treadmill like this would at least mean I’m moving the belt rather than a motor: https://www.woodway.com/manual-treadmills/
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@atoponce said in Wahoo Kickr Core 2 speed and distance:
Zwift and speed is present in the data.
Also note if using Zwift, “speed” is figured by several factors:
- your current power
- the environment Zwift is trying to simulate (hills, flats)
- whether you’re “in a pack” with other riders and drafting
- the virtual bike you’ve selected, different bikes affect things differently
- the use of “power ups” that affect speed (but not power)
In Zwift, your power should never be changed by the game itself. It should always represent your effort as best as the hardware you are using allows. Meanwhile, speed is fictional and a “game element” Zwift can manipulate using whatever criteria they want, and those criteria may have little to do what your effort.
For Zwift, “speed” can be important to “win” aspects of the game, so I’m not saying to ignore it there, but it’s not an objective truth.
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@raven According to the app, the trainer does have an odometer based on tire circumference.
KICKR odometer is a measurement of physical wheel revolutions of the KICKR while powered on. A 700 x 28c tire circumference is used to calculate the distance. KICKR odometer will not match miles ridden on virtual training apps.
According to DCR, speed is baked into the Bluetooth channel.
- ANT+ FE-C Control: This is for controlling the trainer via ANT+ from apps and head units, and includes power & cadence data. Read tons about it here.
- ANT+ Power Meter Profile: This broadcasts as a standard ANT+ power meter, with cadence and speed data baked in.
- Bluetooth Smart FTMS: This is the industry standard for apps controlling the trainer via Bluetooth Smart, and includes ANT+ power and cadence baked in. Additionally, with heart rate bridging, it’ll include that data too.
- Bluetooth Smart Power Meter Profile: This broadcasts as a standard Bluetooth Smart power meter, with cadence and speed data baked in.
- Wireless (WiFi) Direct Connect: This uses WiFi built-in, to apps on the same WiFi network, this includes power/speed/cadence/heart rate data, along with trainer control.
- Zwift Protocol: This is the control protocol that Zwift uses to support Virtual Shifting, and other Zwift-specific features. This is used between the trainer and Zwift, to control the trainers resistance.
So it appears the data is getting calculated in the trainer and it’s broadcast in the Bluetooth channel, but Suunto isn’t reading the data. If the data is there, it would be nice to have.
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@atoponce Yeah, I wasn’t sure if CPS allowed for a speed criteria, and didn’t want to re-read the spec so I just linked it for you. CPS is often used with another protocol CSCS (Cycling Speed and Cadence Sensor), which obviously does report speed.
When you finish an indoor cycling session, you can “edit the distance” for an indoor cycling ride. I never bother to do this, but if you use it to match what you’re seeing in an app, then you might get something you’d like, assuming it takes the “distance” and works out a speed graph over the session duration.
Out of curiosity, what do you expect to learn from “speed” you can’t learn with power data? I don’t know of a “FTS” Functional Threshold Speed aspect like there is FTP to make power zones. Do you think you’d use it as an alternative way to determine TSS?
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Hello,
I am in a similar situation.
I have Suunto Race with Wahoo Kickr Core, the watch detect the Wahoo Bluetooth, but only the power is proposed as information recorded/displayed.
No information of cadence and distance.In my case, I would like to get distance information (Wahoo wheel circumference is set correctly in the trainer), to track bike material regarding wear of the chain, rings, …
How can we do ?
Thank you
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@Dwartus Ah, using it for “wear” info makes sense. With my Stages SB20 bike, I have a belt drive and it’s pretty low maintenance. Could you use simple cumulative elapsed time for this? Either just “do X work after Y hours,” or convert hours to whatever you think your “average speed” is? Or even use cumulative kilojoules?
As I noted above, if you also use an app that gives you a distance metric, then you can try adding/editing that into the final session results. You can do this in the app post-session.
For example, I do sessions using Wahoo SYSTM. It gives a speed/distance result which I ignore. On a recent session I get the following, along with Total Work 468kJ (Wahoo uses work energy in kilojoules for their calorie estimate).
So I could do the following estimates:
1 hour of riding = 500kJ = 30 km (rounding up)Or one can use cadence. In this session I had average cadence of 99rpm so 58 * 99 = 5,742 revolutions. Either just count total revolutions or multiple by whatever distance factor you need.
