Winner of the C race is a B, was the algorithm turned off?
No links allowed….
Sounds like race was using Category Enforcement rather than Zwiftpower rules, where the racer was a C for the former, common scenario for Zwiftpower to be higher.
With CE, you don’t normally get DQed purely for your effort, you simply get excluded from that lower pen level for future events for 60 days, if you new modelled power curve exceeds the lower category threshold.
ZP didn’t even dq the winner, just update my post with the race
pretty crazy that he was allowed to race C cat, plenty of B cat power in his last 60 days…
But if the race is using CE then they shouldn’t DQ after the fact right, assuming the algorithm was working?
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Even though zFTP is predicting a 40min effort, bizarrely IMO, we still get the same 5% buffer used by the old Zwiftpower 20min category placements.
So zFTP needs to be higher than 3.36 W/Kg, which is 238.56W for this rider in question, to get promoted to B.
If you look at their Zwiftpower power graph (which won’t show all their Zwift activities) and play “pin the tail on the donkey,” an extrapolated line from their 12-22min efforts must come out very close to ~240W, give or take a few Watts.
They must be awfully close to a zFTP promotion.
Why wouldn’t ZP do the C win as he’s a B cat?
It’s not a ZP race, it’s a ce race, Zwiftpower categories are not used
This confusion is all Zwift’s making
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Confusing indeed, I’ve been doing this for a couple years and can’t keep track it. I figured ZP would DQ any race where you entered below your ZP cat.
Not if it is a CE race.
Different rules for CE and ZA.
@Gerrie_Delport_ODZ some will run with both CE+ZP, rider has to pick harder cat.
They should not be running both it is completely different rules.
Organizers need to pick the one or the other.
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This are the NEW Category Standards for C and B.
If i could i would run away from CE and ZP Cats.
This is why I’m confused, every one of these metrics is higher than mine, but my suggested category is A
This is WHY i’m using ZP Cat alongside CE…it’s crazy how CE works.
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A good example of the curve calculation that Zwift uses. Both riders zFTP is very close to the A/B cutoff of 4.2W/kg. You’re in A because it’s just above 4.2W/kg, the other in B because theirs is just below 4.2W/kg.
The real question here is why is your zFTP of 260W equal to about your 19 minute power while the other rider’s zFTP of 272W is about their 35 minute power?
The answer is because their power curve as calculated by Zwift is steeper than yours. Their 3 minute power is about equal to your 1 minute power so Zwift calculates a steeper curve which pushes their zFTP out (to 35 minutes). Your curve is much flatter which pulls your zFTP in (to 19 minutes).
zFTP is a stupid name as it has no relation to FTP at all. Zwift would have been better off calling it zCurve or something else because all it does is create confusion of what that number actually is.
It doesn’t help that Zwift says zFTP is “Estimate of your current Functional Threshold Power (FTP), the power you can sustain for a long period of time, i.e. > 40 min.” which is clearly not true.
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From Zwift a while ago:
“The use of zMAP - a proxy of the user’s maximal aerobic capacity - allows us to discontinue using VO2max in the category determination.”
Not that I particularly agreed with introducing VO2 max in the first place but now that it has been removed a little galling that a VO2max of 65.2 (cat A) is shown and not picked up by zMAP ?
To try and avoid more wrong information spreading:
“Their 3 minute power is about equal to your 1 minute power so Zwift calculates a steeper curve which pushes their zFTP out (to 35 minutes)”
NO. zFTP is not related whatsoever with 1 or 3 minute power. You can change your 3 minute power at will that it won’t affect your zFTP.
The real question here is why is your zFTP of 260W equal to about your 19 minute power while the other rider’s zFTP of 272W is about their 35 minute power?
The answer to that is because of how the system tries to determine what are maximal values to do the calculations. If the difference between, let’s say 15 min. power and 20 min. power is too big, it just considers that the 20 min. power is not maximal, and uses only until the 15 min. power to determine your zFTP.
zFTP is a stupid name as it has no relation to FTP at all. Zwift would have been better off calling it zCurve or something
My opinion is clearly biased, my I would just love for some proper independent study to determine what is the closest method from the ones out there 
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This is clearly an interesting edge case for us to analyse.
The reason why VO2max was used initially was to “catch” these cases. It was removed afterwards for simplicity sake. It’s just too confusing to a lot of folks out there.
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This is why I was against trying to explain to people how it works. If Zwift just give the category then they can use nice complex formulas to put racers in the proper category.
It also don’t help that there are 3 different systems being used. (WTRL, CE and ZP)
Most of the negative reaction is from racers that got very good in their particular category and are now forced higher. People don’t come to the forum to thank Zwift that racing got better.
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Hopefully we are closer to end that problem
Most of the negative reaction is from racers that got very good in their particular category and are now forced higher. People don’t come to the forum to thank Zwift that racing got better.
There will always be category boundaries, being CE or a ranking based system, there will always be people racing at the “bottom” of their category. It should be seen as a way to push themselves higher, but I also understand the frustration.