I will be Leading the Friday Steady Ride again.
We have it on Tempus Fugit every Friday but if there is something we want to test i can change it.
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I’d love a test on a short circuit with sprints every lap to gauge the effect that the autobraking might have on race finishes.
I thought the lightweight rider advantage wasn’t just relegated to hills?
Just to take the first example race I opened on ZP (event ID# 3361703).
Is it likely that the 10yr old 39kg rider that won the A’s would do equally well in an IRL race?
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Another round of test events this Friday on Crit City. Regular draft this time.
I prefer to keep it a “placebo” race this time by not saying what has changed.
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We have already established declaratively that lightweight riders do not have an advantage on descents. They do not have an advantage in any way, shape, or form on the flats either. Raw wattage prevails on flat roads, even in a draft. This is absolutely reproducible. For example, at 54 kgs, I can be in the draft of a rather large group and I need to hold a minimum of 0.2 w/kg higher than the average of the riders around me just to maintain position (usually more). In a smaller group, that is amplified. I will give you an anecdotal example, last night I rode with Coco in Urukazi and there were about 13 people in the group. Coco holds between 2.4 and 2.9 WKG. On several occasions on flat roads, holding 3.2 WKG I would observe the group swarming around and in in front of me and had to push closer to 4 WKG to surge my speed not to get unhitched.
Light riders with a high power to weight ratio, can overcome that disadvantage. Children (assuming this was an honest rider) often have VERY high strength to weight ratios. It’s not uncommon for juniors to have FTPs north of 4 WKG “off the couch.” These tend to normalize as they age up
Mine was an honest question. You refer to raw wattage though and then revert to w/kg differences? Your .2 w/kg difference at 54 kgs = ~+10 watts raw. If an average say 75kg rider is doing 2.5 w/kg = 187 watts, and you’re doing 2.7 w/kg at 54kg = 145 watts? If raw watts prevail, you’d have to be up at around 3.5 w/kg to get to the same ~187 watts in order to stay with in the pack.
The example I posted, had the winner with an average of 100-150 watts less (raw) than others in the same race, and the Fine and Sandy course on Makuri I don’t think would be considered a hilly course?
You are ignoring the draft. One on one, I would need to be MUCH closer to the raw wattage of the larger rider.the draft reduces that requirement by roughly 25% But CdA is also a component so it won’t be 1:1 even head to head. Raw wattage is not the only factor in the model, but it is weighted the heaviest. That’s not a lightweight advantage, that’s physics.
Analogize it to riders like Froome and Doumilin in their day… Lighter riders (not the lightest) hold higher w/kg than sprinters or lead out men. They blow them away but can be under their raw wattage.
Zwift is very close to accurate on the flats (assuming a windless existence) EXCEPT for the draft. That’s intentional to allow riders to get a good workout and continue applying power in the group. The double draft option is much more reflective of real world physics and puts riders on a more level playing field. In real life, I can ride behind a 75 keg rider pushing 185 watts at 100 watts.
I don’t have time to look at the race data, but I assume a lot of the race was spent as a pack. A light rider can slot in to a draft like that at 150 watts if they are light enough. I would question a sprint finish, but again variables like timing, terrain, powerups all matter.
If this was, in fact, an honest rider and a child, they are the exception and not the rule. You will see far more examples of what I am saying than 39 kg winners.
I wasn’t ignoring the draft, but maybe there is something to the height advantage of typically lower weight riders. Your anecdote was .2 w/kg versus the “riders around you” which I assumed you meant were also enjoying comparable draft.
This seemingly ignores the draft and considers each rider as an independent entity. It’s not about height in the draft model, it’s about what is required to maintain speed in the pack.
Holding less raw watts is not an advantage. Relative effort is higher than the riders around for lighter riders, often substantially so. This is exacerbated the higher the raw watts of the group. Yumi, for example, holds 2.8 wkg at 215 watts. I need to be at 3.6 wkg just to hang on. In the real world, I would be surfing wheels at Z2 or below.
EDIT: I misread my data while riding, and just double checked: the power I was holding was 3.6, not 3.8 (corrected above). It’s a 10 watt reduction over the power originally posted. I don’t believe this negates my point. I also only hung around for less than 5 minutes because I wanted something more upper Z2 than Z3, I can see a situation where with more people jumping into the group, my power requirement would be reduced as I would not be shuffled to the front or sides with less/no draft as often.
Ahh… I think this all makes sense now. Was your +.2 w/kg anecdote about riding out on real roads and not in Zwift? My own misinterpretation if so.
How does the updated PD work when everyone is descending at 0w for greater than whatever time period you’re looking at for power reduction?
If you and Yumi were to perform an iTT on exactly the same equipment, you’d be just as fast as his 2.8 when you’d be doing around 3.1 w/kg, if you’re 54 kgs.
Sarah, that seems awfully high?
I did 90 mins with Yumi on Sunday on Wandering Flats and my average output was only 2.67 W/kg (I’m currently 56.9 kg at 175 cm). It was a smallish group (30 riders when I joined).
No it’s about Zwift. The real world I would be at a much lower wkg. As I mentioned, raw watts are paramount, but it doesn’t mean CdA and power to weight are ignored in the model. No one would ride together again if that were the case.
The relative efforts between rider in a Zwift draft are much more skewed toward heavier riders because the draft only applies at 25%. The real world does not present a linear relationship between raw watts and speed. It is more parabolic in nature. The higher the raw watts and speed, the closer riders need to be in raw output. This is why you don’t see pure climbers mixing it up in elite crits even with astronomical power to weight. But they can be carried around in a fast moving peloton at a more normative power and speed comfortably.
We aren’t seeing lightweight riders hanging on with packs holding 350+ watts unless they are holding damn near 350 watts themselves. Making their power to weight much higher than their riding partners. Me holding 145 watts with others at 185 watts with 20kg on me is definitely not an advantage, it’s a fraction of a draft benefit.
I was in a group of 8, the larger the group the less drastic, and there is, of course, variation of terrain.
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We were not on am ITT, we were in a small group with dynamic pacing. On flat roads I was around 200-210 watts with occasional drops to 180ish watts as I was at the front and dropping back.
Bear in mind, Yumi goes up to 240 watts
The point I was trying to get across is the gap you need to overcome because of your lower weight is only about 0.3 w/kg. Anything else you experience is a lack of racecraft/drafting ability.
However, he point is moot because it doesn’t reflect the real situation. Terrain matters, group size matters, dynamic power matters. Pack speed is higher than TT speed. It’s a faulty comparison. Zwift cannot be distilled to one equation. It’s a confluence of factors that does not advantage smaller riders - the point of this discussion.
Respectfully I have been on the platform 7 years, I can draft 
…or the messiness of Zwift pack dynamics. The pace partners are so easy to spot that it is easy to see how they themselves make all these weird surges every now and then while maintaining a constant (or near constant) wattage.
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Exactly. Dynamic pacing is far from perfect. It’s quite surgery yet, and the lower your weight, the more noticeable it is because the watts per kilo required to adjust is more drastic than w larger rider.
This isn’t a complaint or a whine, it’s the reality that lighter riders face. It is was it is and I choose to ride within those constraints. Often people who rail against these discussions do not reside in the category and hand wave away these concerns.