Observations and remarks (list)

(Ronald Termaat) #1

Riding now for two weeks on Zwift Mac Kickr

To start with, very nice and addictive


  1. Acceleration way to quick. From zero to 30km/h in a few seconds when giving normal (150 Watts) power.
    Update: Found the problem, on fresh start I get Gorilla power (>1000W).
    1a. With the Kickr (as mentioned in previous postings) the power going uphill is easy to input, but going over the summit the power drops (although I spin quickly). Because of the rapid acceleration, others just fly away from me.
  2. Decceleration. To quick. When coasting for a few seconds it feels like hitting the brakes and you loose the group.
  3. Cornering. Downhill 90 degrees corner without banking. The 90 degrees downhill wouldn’t be possible in real life


  1. You can drive half thru other riders when riding in a group
  2. When passing a rider, only in the last moment you move to the side
  3. When stopping, you stop in the middle and only then drift to the side slowly. Better stop on the side

Power and speed

  1. It would be nice if revs on my bike equals (sort of) the speed in Zwift. Now it seems speed is only calculated by input power. Not sure if Kickr gives input on revs though. When going downhill and releasing the power (pedal slower) you go faster. This is somewhat funny.
  2. When I stop pedaling, the power goes to 0 (it should), but then goes back up to around 40-70 when coasting to a stop. It should stay 0.


  1. Using Macbook Pro Retina i5 2.6Ghz. The visuals are not that great. Would expect more smoothness and more details. For beta it would be nice to have a number showing frame rate and the auto selected graphic detail level.
    Update1: My system uses basic.txt. I now copied medium to basic, increased aniso to 3 and switched headlight on. This seems to work nice in this config and gives a much better graphical experience. Will do a long run tonight with this setting.
  2. Ship and Blimp are pitch black in the night. Windows with lights would be nice.
  3. A few times I saw a rider without a rear wheel.
  4. The squirrel sometimes disappears suddenly.
  5. The speed in which the road moves under the wheels does not seem to make a big difference going 10 or 70km/h
  6. The AI riders could, in my opinion, be more blending in with the rest. Maybe only a special Jersey?


  1. Many times good. But sometimes players go from left to right and do wheelies where Peter Sagan can only dream of. Exit from Zwift and restart solves this seems. Also here on Beta, a number showing Ping rate would help find the issue. Maybe a simple key to toggle Beta data on/off would help find the issues.


  1. Auto connecting works fine. But my RPM/Speed sensor always connects as speed sensor too. But my Kickr is my speed sensor. The Display shows ‘OR’, so I have to disconnect and then connect only as RPM sensor again each time. prefs.xml shows my RPM/Speed sensor id in both the lastspeeddevice and lastcadencedevice.


  1. Checking the log.txt I noticed that the Kickr is set to SIM mode, I thought it should be in ERG mode?
    Update: This is correct, it should be in SIM mode
  2. There are a lot of errors in the log.txt file regarding: ‘GLSL log: Validation Failed: Sampler error:’, ‘NETWORK:error (4) sending player state’ and ‘NETWORK:error (5) sending player state
  3. Many entries like ‘[18:18:19] LEADERBOARDS: Removed entry for Pruett on segment 5340858944
    [18:18:19] LEADERBOARDS: Inserted entry for Pruett on segment 5340858944
  4. More errors on ANT fail, KICKR fail and Power Data unknown.

That’s it for first impressions :slight_smile:

Keep up the good work.


(Christopher Pallotta) #2

Sim mode is correct for virtual riding with your Kickr. In Sim mode, the Kickr creates reistance based on grade, air resistance, your weight and current power to simulate real-world conditions.  

Erg mode is for non-virtual training. There is no simulated grade or air resistance and your weight isn’t factored in the resistance calculation. Erg simply tells the Kickr to create the correct resistance to match your chosen power, or the power prescribed by your workout. 

(Ronald Termaat) #3

Updated the list for correct use of SIM mode. Found back the comments regarding ERG mode again and people that use ERG mode try to take manual control over the KICKR resistance (for using TR eg) but Zwift is now resetting to SIM mode (as can be found in the log files).