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geordanh
12-31-2018, 12:20 AM
Tried out a smart trainer for the first time today. Totally not what I was expecting.

I've got a lemond revolution, which I love. What I'm used to for intervals is holding my rpm and then gearing down 3 or 4 times at an intensity interval while keeping rpm steady. What I was expecting with the smart trainer was that resistance would ramp sharply to coincide with the change of intensity within TR allowing me to hold a steady rpm through the interval.

I was trying out a Cycleops Magnus. It seemed to take forever for the intensity to ramp at the start of the interval, and so to compensate I would increase rpms to try and get the watts up. Every other interval it seemed to create this weird feedback loop where my change in cadence at the beginning or end of an interval would trigger a never ending ramp up or down in resistance. So if I went from 90rpm during sweet spot to 100 rpm to get to the proper power for the intensity portion, I'd be at 110 rpm by the end of that interval because the resistance would slowly decline over the course of the interval.

It seemed to help if I waited a second or two at any change in power, but it wasn't consistent. I was trying not to change gears but admittedly did a few times just out of frustration.

Do they all do this to some degree? Do higher end smart trainers like the kickr have a more seamless/instantaneous interface with TR?

Alaska Mike
12-31-2018, 01:11 AM
I'm a LeMond Revolution owner as well (have two of them), and that was more or less my experience. I bought and returned a couple top-tier smart trainers (Neo and Kickr) and tried a few other wheel-on and wheel off smart trainers, and I've never really liked them as much as my very simple and reliable Revolutions.

I eventually adapted to ERG mode when I did have them, but I would still fight it a bit when I was tired. I'm fairly sure I wouldn't notice it with time, but other issues with the smart trainers just led me to stick with the LeMonds.

Yeah, they're loud, but I've had mine for over 8 years (60-90min/day, 6 days/week, 6 months/year) and only today ordered replacement belts for them. A little cleaning and a replacement cassette was about it for maintenance. I'm not sure a smart trainer would d as well or have the same road feel.

If it ain't broke, don't fix it. Or, if you can deal with the jet engine noise, why dump $1000 on a replacement?

pgrizzwald
12-31-2018, 08:09 AM
If ERG mode isn't your cup of tea, most smart trainers (kickr at least) allow you to switch between modes. So you can switch from ERG mode back to "resistance" mode where your gear selection and cadence are what determine the wattage output. Erg mode is nice for long steady state intervals/workouts, while resistance mode might be preferable for short/intense intervals where you are up or down.

I've experienced what you are describing, though. Once you really get that flywheel moving at high speed/inertia, it seems like you have to keep raising your cadence in order to stay on top of it or keep consistent wattage.

I might try a few workout in resistance mode and report back.

ergott
12-31-2018, 08:50 AM
The Tacx Neo has the quickest response. In fact if my cadence is too low it becomes impossible to pedal (not enough torque). For a big change in power I need the cadence to be over 80 for best results. For steady state efforts I like how fast it responds to slowing down the cadence in order to stand up. If I'm doing hours of zone 2 with 90 plus cadence, it's nice to stand up a few times and it barely nudges the resulting power without needing to shift.

gregblow
12-31-2018, 09:05 AM
I have a Kicker. How do you put it in Erg mode and resistance mode?? thank you for the help with this. i have been using it with trainerroad but would love to use it without all the set up and connection.

pgrizzwald
12-31-2018, 09:09 AM
You can change it through the Device settings in the Trainerroad app, or through the settings in the Wahoo Fitness app. Also, if you use the desktop version of Trainerroad, you can change it during your workout at the bottom of the application screen...there is a toggle where you can change modes.

Nooch
12-31-2018, 09:15 AM
I've found that if I stay in ERG mode I can't make the power I want to make (when I'm reading power from the Kickr), but when I do workouts and use the power off the bike's powermeter I'm much happier (but don't have that entirely flat line of power).

This of course only works if you have a powermeter and a smart trainer..

geordanh
12-31-2018, 11:25 AM
Interesting feedback thanks. Always curious to find ways to spend money on new cycling toys but I'll probably just stick with the revolution.

loxx0050
12-31-2018, 12:11 PM
The thing most new users to smart trainers and erg mode do is try to adjust their cadence/gear to get to the target power levels. That is going to mess with the trainer because in erg mode you hold a steady cadence and the trainer changes resistance to hit the desired target power levels. But, they just can't always respond quick enough to short intense intervals like 5s sprints for example.

I know it took me a few rides to get used my smart trainer erg mode (direct drive Elite Direto). Love the erg mode most of the time except the high power low cadence death grip spiral. That sucks if you've ever experienced it.

oldguy00
12-31-2018, 02:24 PM
I've found that if I stay in ERG mode I can't make the power I want to make (when I'm reading power from the Kickr), but when I do workouts and use the power off the bike's powermeter I'm much happier (but don't have that entirely flat line of power).

This of course only works if you have a powermeter and a smart trainer..


Bit confused by what you mean...

In erg mode, you leave it in one gear, and the trainer will force you to push the power it wants you to based on the erg workout.
If it doesn't, it isn't working properly.

Nooch
12-31-2018, 03:22 PM
Bit confused by what you mean...

In erg mode, you leave it in one gear, and the trainer will force you to push the power it wants you to based on the erg workout.
If it doesn't, it isn't working properly.

you can have zwift read power either from the kickr or from the on board powermeter. when I'm doing a workout in zwift ERG is on and it's adjusting the resistance accordingly, but because I'm having it read off of my powermeter it's not able to "lock" into the wattage. Either as a means of how the powermeter broadcasts or the erg updates, so it's a bit more fluid, though a bit more spikey up and down. Not sure if I'm explaining it well, but that's how I do it and find it infinitely more 'user controlled' than letting the kickr act as the powermeter, which always ends up with me struggling to turn the pedals over at a desired cadence.

MagicHour
12-31-2018, 03:29 PM
Possible you have Erg Smoothing on in the Kickr App? read more below; and/or your PM reads higher than Kickr power, thus making it easier to hit target zone?

https://www.dcrainmaker.com/2018/12/how-to-troubleshooting-power-meter-and-trainer-accuracy-issues.html

I've found that if I stay in ERG mode I can't make the power I want to make (when I'm reading power from the Kickr), but when I do workouts and use the power off the bike's powermeter I'm much happier (but don't have that entirely flat line of power).

This of course only works if you have a powermeter and a smart trainer..

Nooch
12-31-2018, 03:39 PM
Possible you have Erg Smoothing on in the Kickr App? read more below; and/or your PM reads higher than Kickr power, thus making it easier to hit target zone?

https://www.dcrainmaker.com/2018/12/how-to-troubleshooting-power-meter-and-trainer-accuracy-issues.html

I'll check, but I don't think that's the thing. My normal power delivery is spikey -- i don't pedal perfect circles, I don't apply the same power through out the stroke, etc.. the kickr doesn't give me a perfectly straight line, it's a little wavy, but it would be as if it's giving more of a 5 second avg instead of a second by second, which could be my differences. As for not being able to keep up with the power/cadence when fully ERG, well, that's on me..

gregblow
12-31-2018, 04:10 PM
You can change it through the Device settings in the Trainerroad app, or through the settings in the Wahoo Fitness app. Also, if you use the desktop version of Trainerroad, you can change it during your workout at the bottom of the application screen...there is a toggle where you can change modes.

Thank you

MagicHour
12-31-2018, 04:19 PM
Also remember crank/pedal PMs measure closer to the point of power production(legs), whereas with the Kickr reads downstream with the chain/cassettte/pulleys in between. I think I remember reading drivetrain loss could be as much as 5-10w. I’m no engineer, but I’d also think measuring from the wheel would smooth the data plot out a little vs the cranks.

I'll check, but I don't think that's the thing. My normal power delivery is spikey -- i don't pedal perfect circles, I don't apply the same power through out the stroke, etc.. the kickr doesn't give me a perfectly straight line, it's a little wavy, but it would be as if it's giving more of a 5 second avg instead of a second by second, which could be my differences. As for not being able to keep up with the power/cadence when fully ERG, well, that's on me..

smctigue1
12-31-2018, 04:21 PM
I use a Computrainer with TR. I do find it takes a bit longer (5-6 seconds) to find the wattage than the old Computrainer software did. The wattage does seem to drift around a bit but nothing crazy, usually +/- 5 watts or so. I do not need to alter my cadence at all. I found the same thing with Zwift.