Zwift Chat

[Venod]

That's interesting. The guy we had to DQ in DRS said he was also doing high cadence stuff.

Yes it causes a problem, because of the missing readings Zwift gives you some sticky watts without your knowledge, I can't see an easy way round this unless Zwift alters the way it handles input from your PM.
You can of course alter your riding style and ride with a lower cadence, but hard to do after years of spinning.
I have recorded 100rpm for 60 miles outdoors.

 

[bridgy]

This is correct, but from running a few tests it seems Zwift doesn't cope well with high cadence efforts either on my setup, it drops a lot of readings to zero, easiest programme to see this is "Compare the Watts" ( a web based comparrison) it has a tick box to show or isolate zero readings.
It shows the differnce in Watts this makes.
It also makes the power graph look as if your droping your cadence to zero then ramping it up again, when whats acually happening is readings are been missed.

When I posted a power graph from one of your recent rides and pointed out the constant peaks and troughs (down to zero) you said that was just your riding style. Are you now saying you do actually pedal constantly, but all those drops to zero power are equipment misreads? Or are you saying you are riding with stop/start, on/off style but in addition you're also getting these incorrect zero readings?

The ZP data doesn't show cadence to confirm this but you may have that on your Zwift.com ride data

 

[Venod]

Or are you saying you are riding with stop/start, on/off style but in addition you're also getting these incorrect zero readings?

Something close to this.

I would say I ride with high cadence, I do put in the odd very quick spin that I couldn't possibly keep up for a long period but I don't drop to zero as many times as indicated in the graph, so yes not constant, its up and down, but its not stop start, it will be zero occasionally but not as the graph suggests.

 

[Legs]

Something close to this.

I would say I ride with high cadence, I do put in the odd very quick spin that I couldn't possibly keep up for a long period but I don't drop to zero as many times as indicated in the graph, so yes not constant, its up and down, but its not stop start, it will be zero occasionally but not as the graph suggests.

It sounds like your turbo trainer isn't reporting power properly. Didn't you sell a Tacx Neo at a knock-down price recently?

 

[bridgy]

Not exactly this.

I would say I ride with high cadence, I do put in odd the very quick spin that I couldn't possibly keep up for a long period but I don't drop to zero as many times as indicated in the graph, so yes not constant, its up and down, but its not stop start, it will be zero occasionally but not as the graph suggests.

OK well it sounds like you're saying it's both, but it's hard to say without seeing your cadence data how often it's you stopping pedaling and how often it's a data drop out.

Zwift.com ride data should show cadence though if you want to share an image of that from a recent ride - select just power & cadence and the two lines can be compared.

I can see from your rides on ZP (which doesn't show cadence) that on some rides you do have periods where your power doesn't constantly drop to zero and shoot back up again and when this is happening you don't have the sticky watts that are clearly visible when your power is shooting up and down. So I think if you rode in this more normal style (as you would outdoors) you may get far fewer issues - although if it's the equipment doing that and not you that's a whole other problem of course!

 

[alex_cycles]

Well that was a nice way to end it. I smashed the segments in the iTT then went for EVERYTHING in the last race...


View: https://www.youtube.com/live/cj_uYCQouqU?si=9aUqK0Lpn4d04eDK&t=339

 

[Venod]

It sounds like your turbo trainer isn't reporting power properly. Didn't you sell a Tacx Neo at a knock-down price recently?

Yes I sold a Tacx Neo777u, but honestly can't remember how much for.

The Stages SB20 is more convenient if my son wants to use it, easily adjustable no taking bikes on and off, it reports power correctly if cadence is kept below about 100rpm, but constant high rpm results in reading dropouts and sticky watts, its OK if not racing, but not very fair if you are.

 

[Venod]

Zwift.com ride data should show cadence though if you want to share an image of that from a recent ride - select just power & cadence and the two lines can be compared

I am not sure if this would help as Zwift gets power and cadence from the same power meter so I assume if the power signal dips to zero so will cadence.
What I did this morning is put a cadence sensor on my crank and record it to my Garmin Edge, if I get time later I will analyse it on my laptop and see if I can get the cadence from zwift in sync with it.

 

[bridgy]

I am not sure if this would help as Zwift gets power and cadence from the same power meter so I assume if the power signal dips to zero so will cadence.
What I did this morning is put a cadence sensor on my crank and record it to my Garmin Edge, if I get time later I will analyse it on my laptop and see if I can get the cadence from zwift in sync with it.

You won't need to do lots of data analysis to confirm whether it's you or a hardware problem because the power graph is so extreme you'll definitley know if it's the way you're riding (which I thought you'd confirmed was the case earlier to be honest).

If you're pedaling in a natural style (as you would outdoors with almost constant pedaling as opposed to spin-stop-spin-stop etc) then you have a MAJOR hardware issue to get the power/cadence graphs you have with those peaks and troughs. You'd also be seeing constant power and cadence fluctuations on screen on Zwift while pedaling normally which would be really distracting I'd have thought.

 

[bridgy]

Well that was a nice way to end it. I smashed the segments in the iTT then went for EVERYTHING in the last race...


View: https://www.youtube.com/live/cj_uYCQouqU?si=9aUqK0Lpn4d04eDK&t=339

Good tactics to just go all in for the sprints in the TT - especially as you got first in both! I see from ZP that tactic took you from 41st on time to 24th on points. And you presumably had more left in the tank than many for race 2.

Not how I'll be approaching it because my strengths and weaknesses are different but I can see how it worked well for you!

 

[Norry1]

Well I've hardly ridden outside for many months and my fitness (as defined by TSB) is much lower than previous years. Tonight I have signed up for my Club's "Bash" ride which is basically a very fast paceline where everyone is sort of trying to drop everyone else. Soon find out where my real fitness is, gulp.

 

[alex_cycles]

Good tactics to just go all in for the sprints in the TT - especially as you got first in both! I see from ZP that tactic took you from 41st on time to 24th on points. And you presumably had more left in the tank than many for race 2.

Not how I'll be approaching it because my strengths and weaknesses are different but I can see how it worked well for you!

Yes I do that every time in DRS because I am really crap at longish steady-state efforts with no draft.

I really get found out on no draft events (unless they're all anaerobic like the 3 minute ones )

The nice thing is the way DRS puts segments in the iTT is that it gives people like me something to play for. Those 30 points were very helpful . It's pretty much impossible to get 1st FTS in sprints AND win the iTT and that is very deliberate by design.

I wasn't expecting to do very well in race 6, but I surprised myself with my best result of the series

 

[Venod]

You'd also be seeing constant power and cadence fluctuations on screen on Zwift while pedalling normally which would be really distracting I'd have thought.

I don't see this, because I assume Zwift is displaying what it thinks I am producing during the missed readings (sticky Watts and Cadence ?)

These are charts from a ride this morning, the blue ones from the Zwift fit file, the orange from my Garmin fit file, there are zeros in the Garmin graph but far more in the Zwift graph, I don't understand the flat bottom cadence towards the end of the Garmin file it would suggest I free wheeled for 30secs at one point. {I didn't) loss of signal ?
The first blue graph is with zero readings removed.
I think that's it for testing.

 

[bridgy]

I don't see this, because I assume Zwift is displaying what it thinks I am producing during the missed readings (sticky Watts and Cadence ?)

These are charts from a ride this morning, the blue ones from the Zwift fit file, the orange from my Garmin fit file, there zeros in the Garmin graph but far more in the Zwift graph, I don't understand the flat bottom cadence towards the end of the Garmin file it would suggest I free wheeled for 30secs at one point. {I didn't) loss of signal ?
The first blue graph is with zero readings removed.
I think that's it for testing.
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So we're agreed it's your spin-stop-spin-stop pedaling style that's behind the problem and you're not just pedaling normally and having random power dropouts? That's what this seems to show anyway.

 

[Venod]

So we're agreed it's your spin-stop-spin-stop pedaling style that's behind the problem and you're not just pedaling normally and having random power dropouts? That's what this seems to show anyway.

Yes but not completely if you look at the graphs you can see I am having drop outs on some occasions while still pedalling.