ERG issues

Bugs and Support
1

Hi, I am new to Zwift 11 hours in. I’m having some issues around ERG mode in training.

I use a Wahoo snap and always perform a spin down before a session and it is correctly calibrated. I check that ERG is ON when on training rides. I also have a wahoo cadence sensor.

I tend to struggle to feel any difference at all in the resistance when being asked to perform a high wattage. I have experimented and tried to ride at a lower cadence when I should feel the resistance kick in but I don’t seem to notice a change.

I also tend to struggle when being asked to perform low wattage rides at a higher cadence.

I’m at the right cadence but the power is still high. I would have to really reduce my cadence to get to the power asked for.

Another example - ZWIFT is asking for 116 watts at 90rmp. I meet the cadence but my watts are 130, the power doesn’t go down.

From what I understand is that ERG means I only worry about cadence and ERG should do the rest? For example for power of 90 watts in a warm up, I’d probably be doing 60rpm? But Zwift is asking for 85 which makes me produce too many watts.

I stick to the same gear, I would expect ERG to kick in and effect the watts?

The resistance part of the trainer seems to work fine, as on free rides I definitely feel when you are going up and down hill.

Any thoughts are solutions would be great. I am a noob!

2

Hey There, I had a lot of issues around this as well. Some things to check:

  1. Move to an easier gear. I found my trainer has a minimum resistance and if you’re gear ratio is too high it just can’t adjust down
  2. How frequent are your wattage changes? I found that Zwift can take up to a minute, but usually 30 seconds or so to adjust to the new required power.
  3. Stay in the same gear
3

make sure your firmware is up-to-date on the snap. i have a snap2017, and it had some erg issues before one of the firmware updates (though i can’t remember which one).

if you’re in ERG mode, and zwift wants you to do 90 watts at 85RPM, it should be really easy to pedal, and your power should be relatively constant.

if you’re in ERG mode and the next interval starts at a much higher wattage, then you should feel the trainer engage and get harder to pedal.