Shane, did you look at the blog post from Jim’s Basement? That ERG power trace on his example workout shows an interesting pattern. 
Hey @iamholland, @shaunwelch and @iamuwere,
Sounds like you guys are on top of this! That is my ride for sure! Ill address a few things:
- Were working with @shaunwelch (and his wife) to troubleshoot their experience with erg mode. I don’t want to post pictures here of someone’s private rides, but I think @shaunwelch is right, this will get sorted out in this case. He’s been super helpful providing files, which helps communicate faster.
- @iamholland we have tested extensively on lots of different platforms, it’s true my blog post was Dash centric but that’s mainly because we make the Dash and workout control from the Dash is really, really good.
- We’re improving erg mode early on in a ride where the flywheel has not warmed up much (which is especially the case at lower average power rides) where the brake behaves a bit differently when cold. The early jumps in target power can slightly overshoot, but it differs by how you pedal. Right after a target change, we correct erg control using the actual power data from the power meter on board the StagesBike, so these errors should be sorted. The drop-offs @shaunwelch’s wife is using the brakes to overcome will have an improvement in tomorrow’s update. If you look at the picture @iamuwere posted you can see it early (this is also a non-release firmware, but I put it in a blog, so it’s released in a way, no excuses
) - In that ride above, I was doing a lot of cadence variation to test, so when you see those spikes, i am going from about 70 to 95 rpm, which does result in an increase of wattage in the very short term. This is a test ride without much context, you guys are just too internet savvy
One thing I am noticing in early feedback, which may or may not be related to this specific thread, has to do with how a Kickr (which most of you are accustomed to) and StagesBike power will differ in your ride analysis afterwards. When you use the Kickr as a power meter, you are getting Wahoo’s best estimate of power from extensive algorithmic work they have done measured at the rear hub, there is no strain gauge to my knowledge, so there is smoothing taking place. Often the data from the Kickr looks super smooth! The StagesBike measures power from the crank arms with a strain gauge, so it’s giving you real time, unfiltered data every revolution measured at the crank. It’s perfectly normal to see +/- 20 w from a power meter measuring instantaneous power when riding as consistent as we can, we are not robots.
Take this example:
StagesBike (Stages LR PM) vs. Assioma duo in erg mode and a large drop in cadence
The variation here is in a 35-40w window:
Which is totally natural. What you are getting from the StagesBike is the actual instantaneous power from the Left Right power meters on the bike. I’m not bagging on the Kickr, it’s great, but it is not doing the same thing so it’s hard to compare at the 1-3s scale. Measuring power from the cranks and reporting it live is very different than measuring it at the cassette and doing it with math. They can both be accurate, and both will report power on average within +/-2% as proven by lots of testing.
I think there is a lot of space for discussion on this topic, and obviously we are going to always be trying to make the StagesBike even better, so I will keep checking back here. You guys are quite savvy. Looking forward to hearing more feedback, or even rejections of my posts. I can’t ride every bike and trainer out there so it’s great to hear from everyone. Just makes us better.
Jim
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Just a quick correction in regards to power. There is no smoothing when it comes to power matching and setting up resistance. It is still very spiky. The “smoothness” you see is how the data is presented to a user and it can be switched off.
Hey @SomeCallMeTim! I am referring to what the Kickr Power data might look like when you view it in some ride analysis software. Am I still incorrect given that context?
Yes and no.
You are correct if the data representation smoothing is switched on.
If however, the smoothing is off, you’ll see just as many spikes as you would with a standard power meter.
Hope this helps.
Thanks for the feedback Jim. I had a feeling it was doing something like that with the instantaneous measuring of power. Looks more like an outside ride (with my stages powermeter nonetheless). I will say the short time I spent on it in ERG with felt better than it looked if that makes sense. When it got to the prescribed power it was good. My wife uses it more than I do, maybe the spiky line is what threw her off. Her big complaint is that it dropped off to quick where she was freewheeling, and sometimes it seem to be really hard when the power went back up.
She is going to use it tomorrow, I will send any data over after and see how it reacts to the firmware update. It will be 67 degrees here tomorrow so I will be opting outside with my daugher
Thanks again. Its really a well built machine and I expected some firmware tweaks. I am sure it will serve us for years to come.
Ill send info to the support ticket in the next day or two as we use it with the update.
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@SomeCallMeTim Is there something in TrainerRoad that would smooth power data and make it look like this?
Which would be pretty difficult to do with a power meter and very trained pro.
That’s great to hear @shaunwelch, and hopefully the update gives her a better time. We are working on this actively for sure, so great to know whether it makes a difference for her.
It makes lots of sense that the “look” of the ride graph is not similar to the feel of the ride. I think that is a good way of saying what I used 3 paragraphs and 2 pictures to try and say
Talk more soon.
The screenshot looks fairly normal to me. What you also have to keep in mind is that that you also have a large-ish flywheel that naturally smoothens things up a bit.
I get the difference between trainers. I have had KICKR and NEO trainers and they make very different graphs. That part is understandable.
I agree it would be ideal for this to be correct before shipping I have enjoyed hearing from a company react publicly. I think it shows Stages in a good light. Considering this is v1 I am sure all buyers would expect a firmware upgrade. I am sure you have some real horror stories of companies you have given data to and they have no appreciate the help.
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I see this in the exact same way - I’m actually pretty impressed with @jimstemper jumping in here and engaging in such a high quality way, great to see companies engaging with the inevitable user issues that come out post mass launch.
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I am also impressed with Jim’s response here. Maybe this was the wrong place to ask so early in the product release. If so my mistake. I just find other users to be extremely helpful when using a new product. I hope I didn’t make it sound like the thing was a bad product. I expected a couple bugs, that will be resolved. This thing is seriously smooth, quiet and built like a tank, Ipad holder is awesome, USB chargers, etc.
I chose Stages for positive customer service experience in the past with their power meters, the fact they have made bikes for a long time. (Wahoo service was always good too, I just didn’t need the up/down thing).
And the one scenario they couldn’t have planned for and tested, was annoyed wife whos been stuck at home for a month, both of us trying to work from home with a 2 and 5yo… Its a party, let me tell ya!!!
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I received my stages bike last week and got set up but just got to my first ‘real ride’ this morning - an hour Zwift simulation ride on Apple TV IOS. I have a few years and several thousand miles of Zwift on an original Kickr as my point of reference. Overall the experience is very good. Super stable. Whisper quiet - wife walked into the room and said “I didn’t even realize you were riding”. Super easy to adjust height and reach. Smooth pedaling and responsive with the fly wheel. Early release concerns which may just be perception and difference from Kickr:
- Gradient changes seem ‘quick/jerky’ at times - not as smooth as Kickr
- Not knowing what gear your in makes it hard to adjust to gradient changes. Much harder to keep synced between gradient and gears…almost impossible to stay in a group compared to my kickr experience. Racing would be difficult…maybe just need more experience on this platform.
- Perception that gears are not changing when pressing buttons - especially on hoods - but impossible to tell for sure since you can’t see the gearing anywhere. For some reason it seemed like the hood shifting disengaged when gradient shifted to a descent ie couldn’t grab bigger gears. If I would hit the drops shifters it would re-engage. Once again this could be my imagination - anyone else experiencing this??
- Related issue - seemed like I needed to hit the drops shifters on the big gears before the hoods would engage as well at the beginning.
Other notes:
- Super heavy - was a battle for my wife and I to wrestle the bike to second floor workout room
- Set up video is great and easy to follow
- Syncing the bike and crank power meters to calibrate and then connect to Zwift was a bit wonky but eventually magically happened. But needed to reset Apple TV IOS this morning before it would resync after being idle a couple days. Good news - cadence, power, and HR all through two blue tooth connections to Apple TV is great and never dropped.
- Pedals - need to have pedals that install with wrench at axle as bike frame is in the way if you need to come from the back of the crank arm. I eventually got my Look Keos on but super worried if they stick that I wont have leverage to get them off later.
- Still need to try Erg mode
Full endorsement will be withheld pending a few firmware releases and some way to see gearing - but very optimistic.
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Hi Scott,
I seemed to have an issue with the shifters not working at first also, but it was the plug wasnt seated all the way. Not sure if its keyed or not? Anyway, once I fixed that all was well. One thing it says in the paper manual that comes with it is to check if the brakes are working. If so youre good apparently.
Gear indication would be nice, but I think Zwift has to program that in on their end. Hopefully its can be viewed real time in their app. It was hard to tell when you hit a decent if it was working when you hit it 3 times and nothing appears to happen. I found hitting left shifter worked well, assuming i was in the small ring.
I just updated the firmware, made sure it was all working using trainerroad, seemed to be fine, went back to my office to work when I got an angry wife “it wont connect to zwift” Shes pedaling away, nothing on screen even though it was corrected. Cycling power to the bike fixed it… Just and FYI.
One piece of advice if you are familiar with a Kickr, dont watch the graph in ERG mode. Its doing what it says, but it dont look like it with its instantaneous readout. It will mess with you mentally. It feels fine.
I didnt test the firmware as to how it reacts to power changes yet. Maybe tomorrow when it rains, but I am optimistic.
Oh and its a tank for sure… Luckily I had to go down 7 stairs, but the end with the flywheel was heavy as F!
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Thanks for the feedback. I will try the brake test…but I think they are connected as the shifters on the drops work very quickly on descents…just seems like the ones on the hoods go to sleep. I havent updated the firmware yet. I did have to cycle my apple tv this morning to get a power connection on zwift …similar to your wife.
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My wife did a zwift workout in ERG (post firmware update today) and said it was “better” Thats about the extent of the detail I received…
Hi Scott,
I did a longer zwift ride last night. I see what you are saying about the shifter buttons on the hoods vs the ones on the drops. The hoods take a harder push, dont have much of a feel that its been pressed, so you really never know if you pushed it. There were times I did and it didn’t seem to work. Started pushing harder and seemed to work every time. That said, the ones in the drops are bigger and have a nice feel to them.
The firmware update seemed to help a little in ERG, especially in early in the workout. My wife stops and starts a couple times, and she said that was easier. She seemed happy.
Only other tiny issue I have is the cover is a little to close to the flywheel on the right side and would rub if I bumped it. Adjusted it a bit, seems ok.
One recommendation I will make to stages is to sell extra seat masts so each user can have their own saddle. Easy seat mast swap. I see the main benefit of these dedicated spin bikes is for households with different users. Thats really the only reason I bought one; my wife and I both use it and we dont have room for two smart trainers and two bikes setup. We dont have a saddle issue. The saddle that came on it is close to the specialized power arc I use, works for me and my wife has not complained about it, but I see that could be an issue for some.
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It blows my mind that any of these bike builders would spec buttons without a tactile detent action indicating the point of contact. Those buttons exist and serve a hugely valuable service by that action, especially in light of the use case here where knowing the action is completed or not is important and unknown in any other method.
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The hood buttons are tactile so you can feel a push/response…but if the gear doesn’t seem to change there currently isn’t any other method of verifying the shift actually occurred. Hoping the next version of the app or maybe feed to garmin/wahoo head unit will show gearing in the near future if not zwift on the screen. More importantly hoping the shifting on the hoods is actually working consistently.