Level mode in a smart trainer - Zwift Free Ride command

[marco...@gmail.com]

Hi,

I have a smart trainer and I would like to run a workout with several very short intervals which makes ERG mode not recommended. 

How could I set GC/smart trainer to perform such workout in a "level mode" where changing gears would be required to increase power being the workout just a "guidance" of what to do?

I know Zwift in their zwo  supports that by using the "Free Ride" command.

Is there something similar in GC?

Thank you,

[Ale Martinez]

No, GC has ERG and Slope modes only.

If your smart trainer publish a Power channel, you could create another device pairing it, instead of the FE-C channel, so power will be monitored instead of controlled by GC.

[MyJunk Junk]

can slope mode be used for this purpose? eg: Set at like 5% gradient and then you can vary your gears?

[marco...@gmail.com]

But you wouldn’t be able to follow a workout on GC 

[MyJunk Junk]

I'm then confused as to your use case. 

You say you want to be able to use your gears, but in Erg Mode, the changing of gears will basically be useless.

In Zwift, the normal route that anyone rides on are basically such that the app (zwift) would be sending the trainer a combination of wind speed / gradient / air density / gravity values (coupled w/ user weight) and the trainer would respond accordingly and the user will have to vary the bike's gears to ride it just like outdoors. (there's another method, which I'm not sure about Zwift, but GC does all these calculation internally (IINM) and sends a end result target power that would be needed to overcome that windspeed / gradient etc etc.

Hence, in essence, within zwift, when in free ride mode, it's actually in slope simulation mode. 

[marco...@gmail.com]

Freride command allows you to “turn erg mode off” for a given interval still with a power target to be showed and followed.

[MyJunk Junk]

Not sure how/what zwift is sending those commands then. 

[marco...@gmail.com]

U
When you do a workout without ERG all terrain is flat. You can change slopes with Companion app or + and - key on your computer. You can turn ERG on/off in Zwift workout menu. But also during ride with Companion app or press page up key and go to ERG ON/OFF Switch in screen.

[MyJunk Junk]

I tried this on a Zwift workout session connected to a Zwack (https://github.com/paixaop/zwack) instance pretending to be a FTMS based trainer. Here's what I see.

During an ERG workout session, these were constantly sent to Zwack.

2021-07-23 14:59:43.494 node[65791:4841024] didReceiveWriteRequest: <CBCentral: 0x103b05100 identifier = 0D06526B-FF0B-4BE5-881A-D28CAD2DAAF5, MTU = 182> 2AD9

   ftms > [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: Set target power(W): 38w [<Buffer 05 26 00>] +0ms

When Erg Mode is turned off, I see that it defaults to a constant 1% gradient (I noted that in the little map on right hand corner shows 3%) with CRR and CW being sent to the trainer as well

ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: Wind speed(mps): 0 +0ms

ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: Grade(%) : 1 +1ms

ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: crr : 0.004 +0ms

ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: cw(Kg/m) : 0.51 +0ms

Like you said, you can control the gradient using the +/- keys or the OnScreenMenu buttons then I started seeing things like

  ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: Wind speed(mps): 0 +0ms

  ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: Grade(%)       : 6.49 +0ms <--

  ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: crr            : 0.004 +0ms

  ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: cw(Kg/m)       : 0.51 +0ms

  ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: Wind speed(mps): 0 +0ms

  ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: Grade(%)       : 5.99 +0ms <---

  ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: crr            : 0.004 +0ms

  ftms [2AD9][FitnessMachineControlPointCharacteristic] onWriteRequest: cw(Kg/m)       : 0.51 +0ms

Each +/- key denotes a 0.5% gradient change.

So this turns it from ERG mode to SLOPE mode.

So basically your use case is you want SLOPE mode WITH the power target shown on the screen with the countdown timer etc.

I'm wondering - in your short intervals, how short are they? 30s? 10sec? and do you plan on changing the slope % or it will stay constant at say 3%?

[marco...@gmail.com]

Hi, 

First of all thank you for your interest in this matter.

You've got exactly right: I would like the SLOPE (SIM) mode WITH the power target shown on the screen with the countdown timer etc.

Answering your questions:

1-) intervals can be 5, 10 and 15 seconds. Find bellow a workout from Sufferfest called Violator. That is the kind of workouts that would require the freeride.

and his code:

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Violator

Few of us are born sprinters. So Violator is going to make you one. This session takes you through 64 (yes, 64) sprints of 5, 10 and 15 seconds

- 4m40s 50%

- 3m3s 61%

- 1m51s 72%

- 1m3s 83%

- 56s 50%

- 1m3s 94%

- 1m1s 50%

- 1m 107%

- 1m57s 72%

- 4s 135%

- 32s 50%

- 3s 135%

- 30s 50%

- 5s 135%

- 28s 50%

- 6s 135%

- 29s 50%

- 4s 135%

- 30s 50%

- 6s 135%

- 29s 50%

- 6s 135%

- 28s 50%

- 3s 135%

2x

- 30s 50%

- 6s 135%

- 27s 50%

- 6s 135%

- 30s 50%

- 5s 135%

- 30s 50%

- 10s 135%

- 57s 50%

- 12s 135%

2x

- 1m 50%

- 9s 135%

- 1m 50%

- 11s 135%

- 1m 50%

- 9s 135%

- 1m 50%

- 10s 135%

- 1m 50%

- 9s 135%

- 1m 50%

5x

- 15s 135%

- 1m30s 50%

- 15s 135%

- 3m 50%

- 3s 135%

- 15s 50%

- 6s 135%

- 15s 50%

- 3s 135%

- 15s 50%

- 6s 135%

2x

- 14s 50%

- 6s 135%

- 13s 50%

- 6s 135%

- 14s 50%

- 6s 135%

- 13s 50%

- 3s 135%

- 15s 50%

- 12s 135%

- 27s 50%

2x

- 11s 135%

- 28s 50%

- 9s 135%

- 30s 50%

- 11s 135%

- 28s 50%

- 9s 135%

- 30s 50%

- 12s 135%

- 27s 50%

- 11s 135%

- 30s 50%

- 15s 135%

- 43s 50%

2x

- 15s 135%

- 45s 50%

- 15s 135%

- 2m45s 50%

- 3s 135%

- 5s 50%

- 4s 135%

- 15s 50%

- 3s 135%

- 6s 50%

- 3s 135%

3x

- 5s 50%

- 4s 135%

- 3s 50%

- 6s 135%

- 3s 50%

- 11s 135%

- 9s 50%

2x

- 10s 135%

- 9s 50%

- 9s 135%

- 11s 50%

- 9s 135%

- 10s 50%

- 15s 135%

- 15s 50%

- 15s 135%

- 4m48s 50%

------------------------------------------------------------

I also have found a video from Shane Miller - GPLama explaining why we all would need this feature as well a hack to Freeride command to consider.

https://youtu.be/A4aqIzhfUFg 

Thank you very much!

[marco...@gmail.com]

Forgot to answer : I have no intention at all to change slope during the workouts.

Regards,

[marco...@gmail.com]

Hi Ale,

Tks that ("you could create another device pairing it, instead of the FE-C channel") did the job.

Regards,