Fix Drafting

Yup i left Zwift a while ago… i got frustrated with the programers. Everybodys asking them to fix the issues and make it more realistic but instead of making it better all i get are excuses.

Switched to RGT cycling wich has a much better drafting algo, also you can fly on the downhills without much effort. I think they nailed it much better than zwift.

No im seeing the TOUR (virtual) on the tely, i think they fixed all these problems for the pros, you can watch them stop pedaling on the downhills and they are still flying, you can also compare watts when they are in the peloton and figure they nailed the drafting algo. So im pretty sure it can be done right. I jiust dont understand why they dont do it for the mortals on zwift?

Im not comming back to zwift until they fix it.
I hope they do especially now in Covid times

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To add to this, they should add corning physics to the draft/speed algorithms. A large group descending hairpins should not be doing 80km/ph! Riders should be slowed through corners, and larger groups slowed even more. This means an attack over the crest of a climb can be sustained, like in real life. At the moment it is pointless pushing hard on a climb when the pack behind will swallow you up at ridiculous speeds on the descents. RGT slows you through corners and the overall physics model is far more realistic.

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I would say that it’s not perfect but it’s pretty close to doing a UCI race. Averaging 30ish MPH on the flats. A little less if there is some good climbing. If you get dropped you’re not coming back. If you sit in the draft you can nearly get pulled along all day. Maybe there isn’t enough headwind or their virtual CdA is too low since there is no wind.

The speed of a pack might be reasonably close to reality. But I’ve got to disagree that the draft in a Zwift peloton will ever pull you along, even at 30 MPH. Zwift’s group draft is not even close to the strength it is in real life.

Or are you saying that IRL you can sit in the draft and nearly get pulled along? That, I’d agree with!

Try a race on RGT Cycling and see what you think of their group draft physics.

Agree with the draft being off. There’s never a breakaway with pack speeds.I would accept a few draft experimental races. Try cutting the draft down. Double draft, I feel, has been a bit of a disaster.

What do you think of the RGT draft physics? They do have a power penalty for moving up thru the pack which is clearly more realistic. They also have defined lateral position (on Zwift it’s improvised by the client) so if you’re @ the edge you might get less draft. But I’ve never used it except for a brief experiment riding solo (ride suddenly terminated when I tried to switch to my music app).

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That would seem the logical solution, right? But it doesn’t seem to work. The default Zwift draft is already cut down to 50% - apparently it’s 50% of a single rider. Every Zwift race is basically a TT. And I agree that Double Draft only makes things worse, and the group draft is still way too weak.

Have a look at this race on RGT where the group draft is MUCH stronger.

https://www.youtube.com/watch?v=LEcTa0FVY4U

A three rider break forms at about 9:50, and stays away to the finish.

I think it’s much more realistic. Indeed, you do get less draft from the group if you’re stuck out on the edge - just like IRL. RGT has some work to do in other areas… rider positioning included (and also apparently compatibility with music apps)… But they’ve done a really good job on the physics.

Listen to what Ed Lavrarack has to say. He makes an attack at about 44:30 and then talks about his observations of the draft for a few minutes.
https://youtu.be/O69ICNsMey8?t=2666

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@Gru If you agree that the Zwift peloton speed is pretty close to IRL, but you say that the draft effect isn’t strong enough… If the Zwift draft effect were more like RGT’s, wouldn’t the Zwift peloton speed just increase considerably? If so, it would just exacerbate the issue of never being able to get back in the group once you’ve been dropped. Or do you not think the peloton speed would increase?

Eric on ZI did an experiment where everyone in a pack had the same power. The result was a “bee-hive” where riders would shoot off the the front, then slow, but then be immediately overtaken. The result was the pack went faster than a solo rider. This is obviously non-physical, because IRL the pack only goes as fast as the lead rider, who’s almost solo (some benefit from trailing riders, but small).

The problem with Zwift is there’s no collision detection: riders pass thru each other. This is what causes the bee hive. RGT OTOH has an energy for passing other riders. If you did this experiment on RGT, one rider would just pull the whole way, because with everyone @ constant power, the trailing rider wouldn’t be able to get past the leader. This is obviously more realistic.

So it’s more than just the draft effect. Pack dynamics is also an issue.

But do we want it to be realistic? It’s a game, and we want it to be hard. Those IRL races where I just sat in the pack wondering why nobody way up front was pulling hard aren’t the point. Zwift races are intense, and that’s part of the point.

Still, I would like to try RGT.

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It’s an interesting question… With a more realistic draft, I actually think the peloton speed would be slower. Reason: Race tactics and psychology.

With a strong group draft, do you want to be on the front hammering out 300 watts? Or do you want to be a few places back putting out 100 watts and getting sucked along? Unless there’s a really good reason to be working hard on the front (like team strategy?) I know where I’d rather be.

In a Zwift race, the difference in power between being on the front of the peloton and sitting mid pack is much smaller, so it matters less if I happen to end up on the front through the usual churn. I usually try to get with a pack of riders who are honestly a bit stronger that I am, and just hang on to the middle or back of the pack. The stronger riders in the group know that there are blokes like me who are just barely hanging on, so they keep pushing the pace to try to drop us.

In RGT, with a more powerful group draft, nobody ever wants to be on the front of the peloton. It wastes far too much energy. The stronger riders know that they are unlikely to drop anyone by simply pushing the pace of the pack. So they wait, conserve energy, and then attack to separate from the group. Nobody wants to go to the front, and the strong riders aren’t constantly pushing the pace, so the peloton goes slower.

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For the stickyness issue, perhaps one solution would be to use the companion app. A simple toggle button to turn on/off sticky drafting would go a long way to helping this. Now obviously this only helps people who using the companion app, but it’s a start at least.

It justy needs removing compleatly (sticky). I think it only ever robs you of watts ie removes your momentum and sticks you on someones wheel. I cant think of a time i had been thankfull to have it but plenty of times it has hindered progress. I would like to see the HUD speed displayed to 1 decimal place like in TT mode, its a bit dificult to judge how much it is slowing you down otherwise.

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True, we all too…

Because “mortals” need to experiment unrealistic performances really far of the real life physics.
Zwift is the Matrix for the cycling, people have to be happy somewhere… :joy:

Drafting still sucks - if I’m at 3.5w/kg chasing back on and a couple of riders come ‘round me at 2.3w/kg (and how that even happens on the flat off the back of a group is another question), I DO NOT want to draft. The group is gone in a flash. Does anyone from Zwift monitor these feedback forums?

Hi @James_Marshall1

Check this out: New Pack Dynamics [February 2021]?

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Cool, thanks!

So if that’s the new dynamics (I was in a make-up stage) how do I feed back that this didn’t work so well - was in the same group for 10+k and it was mostly fine until it wasn’t

Maybe post in that thread. Give them as much info as possible.

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