Hi Zwifters! I am relatively new to Zwift, I only got two rides in my legs as of today. I bought a Zwift Hub and am running Zwift on an AppleTV. Since don’t own / never owned a road bike I am using my 29" Mountainbike for zwifting. I had the impression that this was a legit thing to do. I quickly discovered that I could not use the supplied 12-cassette for my MTB setup, so I bought a SunRace MZ800 cassette as a replacement, since it fit the freehub body of the Zwift hub. That brought a significant improvement to riding / shifting, but one issue sadly remains: I do feel almost no resistance on flats, even when I run the highest gears. It is OK on climbs, but even then I am running on 5th or 6th gear on the steepest climbs, that I would barely make on 1st gear in real life. I tried setting the trainer difficulty to max and it helped to some degree, however the driving experience was total unsatisfiying since this made pedaling feel “mushy”. I felt like if I was “slipping” during pedaling in the lower gears. I am kind of desperately hoping that there is a solution for this to make training on my MTB setup enjoyable. Everything I saw so far in Zwift seems really great, and I could really, really see myself getting into this quite a bit! I’m loving it so far - if only my bike / gearing worked so that I don’t constanly spin out and can experience some decent, realistic experience when riding on flats and downhill.

@DirtyHarry thanks, already implemented. you can send me a pm and i will send you the new beta or write me on the qdomyos github page

OK, back again. I finally got the chance to test ride the app by @Roberto_Viola today, and I saw some significant(!) improvements. I finally seemed to reach ‘normal’ speeds when pedaling on the straights and I was no longer a sitting duck compared to all the other riders. Also, the inclines felt more realistic. @Roberto_Viola: You app offers a lot of tweaking, however all I am looking for is to get an as realistic as possible experience for my 29" MTB setup. All I changed was the Gears setting / Gears tile. I felt that a setting between 4 and 6 gave me a very realistic experience and resistance in Zwift. However, it didn’t feel perfect, I seemed to go a little too fast on the straights from time to time. I got to admit I don’t fully understand yet how Zwift calculates the speed of the bike and what kind of parameters are important for that (power, weight, cadence, inclination, wind, wind resistance, tire resistance, …). What I definitely do NOT want is cheat with my speeds / perceived speeds compared to other riders and the leaderboards. Is there a ‘correct’ setting that allows me to feel a realistic resistance in Zwift, while at the same time being sure to not cheat in any way?

With QZ you’re not cheating in any way, you’re just adding some strength to your actual resistance. I don’t know what could be the perfect setup for you because it’s very subjective. You should try to give me some inputs based on your feelings, and I can try to transform them into code and settings to QZ. Let me know your thoughts. For example: what do you mean that it’s a little too fast? You’re talking about cadence or reactiveness?

Hi Roberto, Thanks a lot for your reply. With “fast” I was referring to the speed in km/h shown in Zwift. Since switching to QZ, I see much higher speeds than before. It’s a bit hard to explain, but I’ll try: I have no means to measure power on my MTB, so I can’t really compare any real world values to the power levels I see with the Zwift Hub / in Zwift. However, whenever I tried to pedal at a certain perceived resistance and cadence, I felt that the speeds indicated by Zwift were much lower than to what I would have guessed. For example, I believe I have a quite resonable “feeling” for what effort it takes to drive 30 km/h on a straight road in real life. I’d have to pedal with quite some effort on the higher gears. Whenever I tried to put the same effort into Zwift, I barely got faster than 20 km/h (according to the indicator on the screen). I always wondered if that had to do with the way that Zwift calculates speeds, with my gearing, the circumfence of my wheels, etc. I think though it’s coming straight from the power input measured by the Zwift hub? Now, back to using QZ: When I use QZ, I see much faster speeds at pretty much the same efforts that I put in. When I use a QZ Gears setting of 4 or 6, it pretty much matches my feeling regarding the speed I would probably achieve in the real world as well, maybe even more. That was the reason why I asked you if I was maybe “cheating” a bit, since all of a sudden I felt like I was even “too fast” compared to “much to slow” for the kind of effort I was putting into it. I was climbing some 3 % inclines with around 25 km/h yesterday, I don’t think I could do that that easily in real life. I hope you can get what I mean… If not, let me know, I’ll try to find a different way to say what I’m experiencing. Thanks a lot for all your help. QZ literally transformed the way I can experience this whole Zwift thing! Kind regards, Harald

when you’re talking about QZ speed, you’re talking about the Speed tile that you see on qz? If so it’s because by default, QZ is calculating speed based on your cadence. But you can enable the speed calculation based on power (as zwift does) enabling the “Speed based on power” setting. If instead you were talking about the Zwift speed, is because, using the gears tile, you’re increasing the resistance on your trainer and so you’re creating more wattage and so more speed. Let me know which one is true and we can go on :slight_smile:

Hi Roberto! Thanks for your reply. I was indeed referring to the speed indicated in the Zwift app. I understand now that thanks to the increased wattage I am able to put into the trainer by using your app, I can now reach higher speeds on the straights, more equal to what I am used to in real life. Wonderful! I’ll play around with the Gears setting in QZ a bit more to find the right resistance setting for my gearing setup, and then I’d say this case can be closed. I can finally be a happy Zwifter. Thanks Roberto! By the way, just in case somebody else is wondering about that as well: How does Zwift actually calculate speed figures based on your pedaling? I thought it’d have to be connected to your power and cadence numbers. That brought me to another point: How is measuring cadence actually possible with no extra sensor and not knowing my gearing? So I did some reading on how trainers are able to calculate (virtual) cadence figures. If I understand correctly, cadence numbers can be derived from rhythmic variations of the power input. If that is so, I was wondering if Zwift used this information together with the power input to calculate what kind of gearing is (theoretically) in use and deducts the rotations per minute of my avatar’s wheel. Together with tire dimensions, weight, height, drag coefficient and so forth, that would allow to determine how fast my avatar goes in Zwift. It seems though that Zwift more or less purely relies on the power input (see zwiftinsider .com /how-does-zwift-calculate-my-speed/, /zwift-speeds/ and /garmin-zwift-distance/ for more; Sorry for the formatting, I can’t seem to share links in posts yet) and all the above is not relevant for the speed shown in Zwift at all. If somebody has a more in-depth explanation of how this actually works, I’d be interested to know!

[image] Harald: It seems though that Zwift more or less purely relies on the power Zwift only use power to calculate speed. [image] How Does Zwift Determine My Speed? Bugs and Support How Does Zwift Determine My Speed? For Wheel-on Classic Trainers: Zwift takes the wheel speed broadcast by your speed sensor and the power curve (see example below) of the trainer you select on the Pairing Screen and converts that to virtual watts, also known as “zPower”. Your in-game speed is de…

There is a YouTube video from GPLama about how trainers estimate cadence

Hi @Roberto_Viola I have just bought a Zwift Hub and have the identical issue as @DirtyHarry so was delighted to see your app! I’ve just bought your app to see if that helps but I’m having trouble connecting the app to the hub. Before I continue troubleshooting, I just wanted to check that I have the right version or has the Hub support not be publicly released yet? I have v 2.11.96 I expect it’s just me, but I wanted to make sure! Many thanks, Craig.

hi @Craig_Smallman the zwift hub support is in beta. write me on the email that you find on the qz app to receive the beta let me know!

Thank you Roberto. I have sent an email (hopefully to the right email address I found via the app)

New to Zwift (Hub), trouble with MTB setup and resistance

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Gerrie_Delport_ODZ (Gerrie) December 30, 2022, 9:09pm 35

Zwift only use power to calculate speed.

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New to Zwift (Hub), trouble with MTB setup and resistance

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