How to get true speed reading from Zwitf?

I have a ThinkRider X7 smart trainer which has RPM, Power Output and Dynamic resistance. In Zwift, when going up an incline, I feel the resistance increasing, my power output going up and although I’m keeping the same gear and cadence, the speed displayed in Zwift goes down. How can I configure Zwift so it doesn’t fake the speed but uses the RPM data from my trainer?


Although it says “as it should be”, personally, I don’t agree. On a Smart trainer with dynamic resistance, the revolution of the wheel should always represent the speed and the resistance affects your effort. You’re drafting behind someone? Fine, DROP THE RESISTANCE, which is basically what happens when drafting anyway! It’s a big head wind? What happens in real life? The resistance increases, forcing you to push harder to maintain speed. Guess how can this be done on a smart trainer with dynamic resistance? Yep, increase the resistance. Don’t fake my speed! Adjust the resistance accordingly! You decide to try a 15lb carbon bike instead of that 30lb steel bike of yours? Where does it matter most? Acceleration. Drop the resistance there (or the opposite if you’re trying that 30lb steel bike). The only time resistance can’t be used is going downhill, but dropping resistance to bare minimum should allow me to go pretty fast on high gear with almost no effort. Which is basically what I do downhill anyway.

So, if Zwift can’t do it, anybody knows another app that would give me realistic speed and adjust the trainer’s resistance to simulate the environment? Thanks.

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Is your Trainer Difficulty setting at 100%?

RGT did that under some circumstances, but the company cancelled the app. Not sure if others do.

I tried to look for this setting but can’t find it. Where is it located?

This is essentially a feature request that many of us have been asking about this year in particular (unsure if it’s been asked before, maybe it has).

Specifically the altering of resistance on different surfaces.

That said OP, I don’t think the accuracy of a dynamic solution here would bring your distance readers into alignment; that’s something you’re just going to have to get over.

Trainer difficulty is the slider in the main settings menu:

indieVelo changes the trainer resistence based on draft, wind, braking etc.

Note that turbo trainers generally can’t handle this acutely enough for it to be a one-to-one match. As a bare minimum, you need a motorized flywheel.

Totally agree, speed is how many times that back wheel turns in a minute, multiplied by its circumference * 60 and that is physics, and surely that is the speed that the trainer is sending to zwift

I’ve tried dual recording when using IndieVelo and the distance recorded on there and on my Garmin get out of sync quite quickly so it seems like there’s still some interpolation going on. FWIW the Garmin “over-records” distance when I’m climbing and “under-records” when I’m descending.

No, no it’s not. I’ve been through this painful discussion a lot in the last week.

Power is sent to Zwift. Power is (sic) accurate. If you change the input to speed, you are then saying that your power is inaccurate.

Trainer manufacturers do not develop the hardware for accurate speed, just extremely roughly to get a ‘inertia feel’. If a software platform sent exactly correct resistence values for all moments in the game (draft, gradient etc) the speed would still be wrong. If you then extended it to multiple users in a multiplayer environment, it would be an absolute circus.

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The garmin is wrong. It is taking speed from your trainer, which is wrong.

Yeah - I edit the Garmin Connect result.

Well duh, I wasn’t connected to my trainer when I tried. I’ve changed it to 100 now. Although it’s nice again outside so I took the bike off the trainer and will resume biking outside for now. Needed the bike on the trainer for a challenge and found out Garmin doesn’t recognize Zwift virtual rides for challenges :face_with_symbols_over_mouth: Fortunately, there is an easy workaround.

I think some of them have started to count; or they added to the pile this year that include virtual / indoor rides.

I’ve noticed I started to get Garmin badges; and formerly never riding outdoors until this year, I started picking up badges.

I just ignore the Garmin challenges in general; it’s like Zwift’s challenges to me now… too many to keep up with and you get nothing out of them other than a fake sticker :sweat_smile:

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