The Watt Wasting Window: a Demonstration

Watch for a Zwift Insider post all about this on Monday, April 22nd...

[@darrylperry6029]

I’ve tried riding at the minimum amount of watts to stay in the draft, and like your video, it was a lot, so I’m not surprised. Still, it’s very useful information. Thank you.

[@nordy643]

You should do this with a 3rd rider where you ramp the 2nd rider watts and see what happens to what power 3rd rider needs to hold to stay in position 3.

[@ZwiftInsider]

Perhaps I will. My guess, though, is nothing will happen to the 3rd rider. It's all about rider speed in this case, and since the 2nd rider isn't changing position, the 3rd rider wouldn't either.

[@SteakandChains]

I feel like this is a great demonstration of a video you did a while back about how sometimes in group rides you need to double ish the power just to keep up or catch up if you fall off the back. Great video!

[@ZwiftInsider]

That's a different scenario altogether, though. What you're talking about just shows how much faster you can travel in a pack vs as a solo rider under the same power... I think!

[@SteakandChains]

@@ZwiftInsider this is the video I was thinking of. From what you’ve demonstrated and my individual experience I feel like there’s a zone in drafting where people can get stuck. kzbin.info/www/bejne/imWcpH55ZcaCmZosi=FcB5_ARyZ8t57R9K

[@MemeLord-fx5pd]

TTT are my favorite racing on Zwift right now. The dynamics have been changed enough to make it seem like you’re able to overcome a lack in FTP as long as you know how to exploit the game code. But that’s just me convincing myself to suffer for 40 minutes on a Thursday

[@Ad-my9kg]

Does this not also illustrate that the "draft -watt savings" is not correct? Whilst rider 2 was at 231 watts the watt saving shows as around 101. When rider 2 is put up to 293, the watt saving still shows up to 109. Does this not therefore suggest that the riders total watts, if they were not in the draft would be 402? Or am I misunderstanding the display?

[@ZwiftInsider]

No, you are correct. The draft meter says "w savings" on it, but that can be confusing if you do the math like you did. What it's really showing is "because of your current drafting position, you can travel at this speed but with X fewer watts than if you weren't drafting." What it's NOT showing is the extra watts you may be putting in, which are being wasted. Those don't figure into the Draft meter at all. So you can be sitting in the draft "saving" lots of power, while also riding inefficiently and wasting power because of how Zwift's pack dynamics work in this scenario. A bit mind-bending, but there you go!

[@markgunn6680]

​@ZwiftInsider It's still not that accurate though as you should be able to save 100w in the draft but the minimum was actually only 70w until you started to get dropped

[@stevej_on_your_MTB]

I've suggested that if Zwift pushed you out to the side and into the wind when doing more watts than needed, it would make this obvious. I'm not sure this can be done though as some riders are using steering and will try to get back into the draft position.

[@derekkuhl]

Awesome data. Thanks!

[@MrJhockley]

This doesn't work with the Robo Pacers. I find i have to match and often exceeed the power when sitting in the pacer group or i'll get dropped.

[@psymanj73]

Whatever I do, I am the Bot behind at the higher watts 😂

[@djconnel]

RGT had an indicator telling riders how much power they needed to exert to hold draft.

[@roadcyclist1]

RGT is trash so it is irrelevant.

[@TySchmidt-xh9ij]

Interesting! Any TTT riders care to share how they counteract this? Like the lead rider stops pedaling for 1-2 secs after pull? Or 2nd rider shouldn’t ramp up to pull target before their pull starts?

[@ImGlossy63]

Good info for sure… just need to find a good team to join now to get some nice TTT experience.

[@mikeheath-fe6iv]

EVO has a great team racing ethos and plenty of choice of TTT teams at various levels and times of the day.

[@ImGlossy63]

Thanks Eric, I’ll look them up.

[@richardneil5202]

I'm failing to see how this is a surprise to anybody who has done group/TTT rides on Zwift for more than a few hours. The drafting is pants (that means rubbish by the way!) - always has been and probably always will. Comparisons to IRW riding are useless, Zwift is a game and has to be accepted for what it is (or isn't). Having said that I miss RGT and its "wasted watts" display😢

[@HoldenAdventures]

Any chance this looks different in 1st person view?

[@najmifauzi8310]

Hi, i always wondering how did you run the test? is that any additional apps to simulate the power? or any specific option from zwift app? Thank you

[@ZwiftInsider]

Additional apps, hardware, and other dark arts...

[@user-mz6yl7yl7n]

Eric, One of the reasons I have never loved Zwift is that it has always felt a little "dead". Besides the delay in power onset, there has also been this seeming lack or correlation between power input changes, and resulting action in more scenarios than this. You have done well to demonstrate and quantify this, but my belief/ impression is that the "characteristic" goes far beyond this limited case you show. Have you tested to see if there is any other kind of power [bracketing] in larger group situations?

[@ZwiftInsider]

Harder to test in a group, since the group is dynamic by nature (I have no way to simulate a group of, say, 20 riders at a particular power level). But power changes seem to move me back and forth in a pack just fine nowadays, with Zwift's current pack dynamics. It's just getting into the wind that is extra tough!

[@user-mz6yl7yl7n]

@@ZwiftInsider Thanks for the reply Eric. I also just found your prior videos on this very subject and the solution since 4.1.1 so might give Zwift a try again.

[@foreveryoung8097]

I’m sure this also happens at least at the back of the group. Also being a light rider I can’t move around the group just fine like Eric does.

[@hexhausted2476]

So you should ride constantly with the close the gap 2m signal on your screen to save a lot of watts. I have wasted a lot of watts….

[@ZwiftInsider]

Mind you, that's only in this particular scenario. If you were in a large peloton, you can float around in the group very efficiently. But if you're just one rider drafting behind a front rider... chances are you're wasting watts if you're snugged right up against their back tire and there's not close the gap message.

[@darrengreen7906]

What would the minimum be for the 5th/6th rider in a tTT? same as the 2nd rider if all strung out? Well oiled teams could min/max with good discipline and practice.

[@ZwiftInsider]

Haven't tested with 5th/6th, but here's 4 rider tests: zwiftinsider.com/tt-drafting-pd41/

[@timwatkins3828]

Key data point. Riders are same height and weight. So not real life, does a taller rider behind or in front make a difference? does 10-20 kg's make a difference? I've seen 100kg riders putting out more watts, same wkg as a 75kg rider but be pulling away on flats.

[@ZwiftInsider]

That's a different test entirely. But you could do this test with a larger rider ahead and you'd get the same conclusions - there's still a watt wasting window. You might be interested in this: kzbin.info/www/bejne/eHiTgqeBi95ro5o (post coming on this topic next week).

[@roadcyclist1]

I thought this had been well known for many months.

[@marcorufer2342]

what surprises me is that this is no longer the case in the pack according to your video: kzbin.info/www/bejne/aaiyioSihZdjqKcfeature=shared What is the real difference?

[@ZwiftInsider]

The difference is moving around in a pack vs moving to the front of the pack (putting your nose in the wind). Zwift lets you move around in the pack easily, but if you want to go to the front, you need to be putting out enough power to match or beat the current front rider's speed. That is, unless you carry momentum into it. You can accelerate from the back of the pack then ease up and still coast off the front. You just won't stay there long.

[@lost1313]

Thats flawed- they should fix it

[@ZwiftInsider]

Easier said than done. Question: we all agree the rider should be able to hold the wheel at, say, 230W. So what should happen, in your opinion, at, say, 275W?

[@lost1313]

I am not an expert, but my nature logic would say that I should start close the gap- a dead window with about 20% from overall watts Sounds irrational to me. Actually because of the drift it should be possible to overtake if I hold 275W against 300W and than I should fall back again relativ soon.

[@ZwiftInsider]

@@lost1313 outdoors if you went to 290W in that situation, you'd ride into the other guy's back tire and crash. Or you might veer a bit and start to come around, but then you'd hit the wind and be kept from overtaking. That is, unless you were carrying momentum into it. Momentum might let you slingshot around and get to the front... but you still wouldn't stay there long. Plus, in this video, the second rider doesn't have any momentum.... I think the way Zwift has it working, in this particular scenario, is probably the best solution, since we can't run into each other in game.

[@lost1313]

@@ZwiftInsiderstill, you should close the gap, I mean if you like to overtake you could push 275W and when you closed the gap increase the power. Atm you need to Push more w/kg than the guy who gives you the drift. Not the best solution when it comes to Racing. But I guess something is behind, why Zwift decided like this, it’s too obvious

[@ZwiftInsider]

@@lost1313 if you match the front rider's power (assuming you're the same height/weight/bike setup) you'll ride right next to them. If you're just below their power (and thus wasting watts) you'll sit right on their back wheel but not come around. Ease up a bit and you can play with a gap of 2-3 meters. That's the efficient place to ride.

[@occyman]

Good video Eric but sadly many Zwift riders have never raced IRL but expect Zwift to be exactly like IRL. It’s just a video game - not real at all, the racing results are not real either.

[@Evaso_CC]

Yawn….