Resistance and speed issues

Hi all

Looking for some Help and advice.

When i start a ride my wattage and cadence start as shd but when i go through the gears it doesn’t increase an i just end up spinning out I’m using a wattbike and everything works fine on the wattbike app I’ve checked all my internet connections and everything is fine with them and its the same if use it on different devices even on my phone network any help would be much appreciated

Cheers James

I am new to Zwift and I have noticed that sometimes Zwift will not increase/decrease pedaling resistance as function of the road gradient. I find it really annoying when I start up a grade with a constant cadence only to see my speed decrease. I am so used to wanting to “feel the grade” and decide to either downshift, or put out more power to maintain a specific cadence. Same thing with downhills, I want the resistance to drop and then decide if I want to give my legs a rest or shift into a higher gear and enjoy the speed.

Note: I have tried a couple of rides on Rouvy and the feel of the road grade works perfectly. Really makes the riding experience more enjoyable for me.

Hi Stephen,

Ive only started having this issue the last 3 days even if the gradient is at 0% i can get in 22 gear in my wattbike and it just keeps spinning out i cant get over 50watts or 18kph

Cheers James

Still experiencing this non varying pedal resistance problem. It doesn’t happen on every ride and I have no clue as to why it happens, let alone how to mitigate it. I am using an ANT+ dongle with my Window10 PC and verified all the connections that read data and control the trainer (Wahoo Kickr) are connected via ANT+. Power cycling the Kickr and relaunching the Zwift program has had no effect. Also, I never had this problem using Rouvy. The lack of varying pedal resistance based on road grade is a real Zwift negative. I will be “moving on” if it continues to be an issue.

The last time this happened I immediately fired up the Wahoo App and went into resistance mode; changing the resistance manually works just fine. Therefore, the problem appears to be with Zwift’s ability to control the trainer. (Yes, I have tried BT and even turned off BT when using Ant+.)

It there a log file (debug mode) that records the data and commands sent between the PC and the trainer that can be inspected to see if the trainer is actually being sent valid resistance change commands?

I am not interested in working around the problem with some band-aid solution, but finding out what the root cause of problem is so it can be properly addressed.

Do you pair as ant+ FE-C

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Are you a Zwift employee in a position to effect a resolution to this problem? I do not want to waste your or my time if it does not to led to accurate understand of the root cause and a solution. I am willing to be shamed if the root cause is me, a user who cannot follow simple instructions, or has unrealistic expectations.

Regarding connecting the “controllable” trainer using ANT+ FE-C: I did capture a snapshot of the Paired Device screen, but it appears you cannot insert an image in a post. I verified the “Controllable Trainer” was successfully paired using ANT+ FE-C protocol.

I did some poking around and discovered Zwift keeps settings and log files of ride activity in …\document\Zwift\Logs. Even though the log file is “man readable” I am in no position to decode its meaning.

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Few things.

Make sure there is no other app that is connected to the trainer via bluetooth.

Do you see power numbers change in the pairing screen while pedaling?

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I did a couple of experiments today which appears to point to where the problem lies. I removed my ANT+ adaptor from the computer and forced all connections to be Bluetooth (BT); pedaling resistance varied according to road grade.

Reinserted ANT+ adaptor and noticed Zwift appears to have an affinity to connect via ANT+ over BT. Initial attempt to unpair the “Controllable” device and pair it with the BT interface didn’t work because only the ANT+ FE-C interface appeared in the selection list. It wasn’t until I unpaired the Power sensor and paired it to BT did the BT interface appear in the “Controllable” interface selection list. Finally, I was finally able to get varying pedal resistance and my ANT+ based heartrate monitor working at the same time.

Clearly, there is something amiss with ANT+ FE-C controlling pedaling resistance on the trainer (Wahoo Kickr V5). The Zwift log file should provide a clue as to who is at fault: Zwift software or trainer firmware.

Please isolate where the problem is. If the problem is with the Kickr please notify Wahoo of the problem. Zwift has a lot more influence reporting a problem and getting it fixed than if I reported the problem.

I have narrowed down the problem even further. I tried out BigRingVR. BigRingVR’s app only supports ANT+. Got the same behavior I was getting in Zwift; pedal resistance did not vary with road grade while using ANT+. Went back and reviewed all the Amazon reviews on the ANT+ dongle I am using. Sure enough, I found 1 review out of the 400+ that says dongle does not support ANT+ FE-C (Fitness Equipment Control).

[Here is where I would have inserted a screen capture of the Amazon Review, but I am not considered worthy to add “mutli media” elements to a post.]

I have contacted the manufacturer (CYCPLUS) to confirm the dongle does not support FE-C. CYCPLUS says the device supports FE-C. However, BigRingVR set me a link of analysis of the device done by the fitness equipment manufacture Tacx (t a c x f a q x . c o m /knowledge-base/cycplus-ant-stick/). Tacx found the device lacks important functionalitywhich causes problems controlling fitness equipment.

[Damm, not even authorized to include a html link in a post.]

So why did I think it should have worked? Consider the following screen capture:

[Here is where I would have inserted a screen capture showing the “Controllable” being connected via ANT+ FE-C]

Zwift appears to have successfully connected to the “Controllable” part of the Wahoo Kickr using the FE-C protocol. It connects something but Zwift clearly never validates the connection for FE-C operability. The log file probably is full of Zwift sending commands to increase/decrease pedaling resistance without ever getting back confirmation that the command was accepted. Zwift should have generated an error/warning right from the start indicating there is a problem.

I dont agree with this - the dodgy Ant+ dongle either adheres to the ANT FE-C protocol standard or it doesnt - in this case it clearly doesnt. Its kind of the whole point of having protocols in the first place.

If Zwift had to code for partial compliance to ANT and all the possible permutations of data not coming through, or partially coming through, or mixed data from alternative device streams coming through etc , well, it would be grinding to a halt more than it is already.

I was not suggesting that Zwift code for partial compliance in an attempt to workaround “doggy” hardware/software. What I am suggesting is that Zwift preform a quick validation to insure the connection supports all the features Zwift is dependent on. I view this is an opportunity to improve the Zwift experience for its users by identifying “issues” and alerting the user of them. Having things not work, or stop working during a ride can be very frustrating experience. There needs to be a better (intelligent and simple) way for a user to determine the cause for anomalies. A utility that parses the ride event log file, identifying anomalies, would go a long way in helping pin point problems.

[quote=“Stephen_G5, post:11, topic:517311”]
I was not suggesting that Zwift code for partial compliance in an attempt to workaround “doggy” hardware/software. What I am suggesting is that Zwift preform a quick validation to insure the connection supports all the features Zwift is dependent on. [/quote]

OK, thats not asking for development to accommodate non-compliant 3rd party device :+1: