Zwift Power Category Determination Changes?

Based on my results three weeks ago in the ZRL TTT I was auto-upgraded from B to A for exceeding the category limits (as were two teammates). Then, a week later, without any additional racing results and none of my top performances falling outside the measurement window, I suddenly showed as B again (no weight change, either). We checked to see if I could race with my B team and were told that I could not resume racing with them since I had been upgraded during this round to A, even though I show as B again on ZP.

I don’t understand what caused me to drop back to B again. My 3 best 20-min w/kg results of 4.3, 4.2 and 4.2 were within the last 60 days. Taking 95% of these three averages to 4.03 w/kg, so shouldn’t that designate me as an A?

Link to profile?

1 Like

For some reason that last one isn’t being included in the calc (4.103w/kg). Odd.

Yeah the 95% at 283w is missing :man_shrugging:

For some reason that is showing as a group ride not a race

maybe @James_Zwift can look into this. he get his upgrade.

I’m not sure but link below is similar. Is it because the race was a team time trial which doesn’t count for Category calculation or ranking points ?

rare but old ZP glitch. it’s not TTT specific

1 Like

Makes sense - ZRL isnt a TTT anyway, just a team event with mass start and no reason whatsoever that they shouldnt scrutinised like every other ZP event for Cat purposes.

it happened to me once in an innsbruck KOM race probably two whole years ago and i’m not sure if i ever bothered to ask why, i’m pretty sure the .fit file processed correctly too. well, if you can do it once, you can do it twice so you will get your A upgrade soon enough OP, if you really want it.

i’ve done about 800 events and i only remember the one instance of it happening so it is rare

1 Like

I just had a quick look at the post Ian referenced. The profile mentioned in that post has the same issue as did a few other top racers in that particular event. All were +4w/kg (didnt bother checking further) so if it’s you high-power folks targeted by this bug, I’m in no danger :rofl:

I’m fairly sure this race was a TTT


The format for ZRL does indeed include TTT’s for some events and two week’s ago that’s what it was.

1 Like

Ah right, I only watched one yesterday and was mass start so assumed all were. Another school[ed] day :slight_smile:

I came here through the quote from my topic: I think it’s worth mentioning that there are a couple of strange inconsistencies (or questionable “designer choices” to put it in a more friendly way) within the current Zwiftpower FTP calculation. I have mentioned these in the quoted topic: Bug in Zwiftpower calculating categories


  1. Zwiftpower will ignore 20 minutes efforts if 2 efforts among the best 3 efforts were done on the same day. Seems questionable to ignore such an effort if a rider proves more than once in a day that he/she should actually be in a higher cat. :face_with_raised_eyebrow:
  2. Zwiftpower might generate the incorrect FTP in absolute watts when a rider has been changing his/her weight. To calculate the estimated FTP, the script will not pick the best 3 efforts in absolute watts, but rather pick the best 3 w/kg efforts (which due to changing body weight does not have to be the set of best 3 efforts in absolute watts as well), convert those to absolute watts and then calculate estimated absolute FTP.
  3. Zwift event administrators need to set a certain TYPE_RACE tag for a Team Time Trial event in order to have Zwiftpower include the event for the FTP estimation. This is not consistently done and as a result sometimes TTT’s are ignored for FTP estimation.
1 Like

The reason is exactly as I stated in the other topic, the TYPE_RACE tag is not set for this Team Time Trial with eventID 3239049.