Zwift Chat

[steverob]

I may also buy speed and cadence sensors to partially 'smarten up' the dumb trainer, though I can't see how they could give an accurate measure of power, given that Zwift would not know what resistance had been selected, what type of tyre was being used, the tyre pressure, or how hard the tyre was being pressed against the roller!

If the trainer is on Zwift's known supported list (and there's quite a few of them), then they have a power curve for each model which roughly matches what power they expect you to be doing if you are going a certain speed. When you set it up it also states a recommendation for what resistance level you should set the bike to (e.g. you're not meant to adjust it when you're going up hills etc.)

Some people say that despite the estimation, the figures Zwift produces can still be reasonably accurate if you pick the correct trainer, but even then you will find that your watts will be capped at a certain number (could be 1200, could be 400 depending on the trainer) to stop there being a chance of crazy numbers being produced accidentally. Also most races won't allow you to enter with a "dumb" trainer either for fairness reasons.

Here's a good article on some of those points that probably explains it a lot better than I could! https://zwiftinsider.com/virtual-power/

 

[mjd1988]

Id like to feel that bad and still take top step

Thing is I didn't win...I'm pretty sure the person in second beat me by 0.02 seconds...but on zwiftpower I beat him by nearly 50? Bit confusing.

It was a rough race as mass start, mixed group of bs and C's at the front, but nice to be competitive on a climb!

 

[Peter Salt]

I may also buy speed and cadence sensors to partially 'smarten up' the dumb trainer, though I can't see how they could give an accurate measure of power, given that Zwift would not know what resistance had been selected, what type of tyre was being used, the tyre pressure, or how hard the tyre was being pressed against the roller!

I've set up a dumb trainer on Zwift before, for a kid's bike. It asks you about the model you have and the tire width so it can be more accurate. Still, it's a rough estimation.

 

[Legs]

I had been considering a range of different smart trainers which are available now, but I eventually decided that I preferred to wait for a JetBlack Victory.

I got an email last night saying that JetBlack are taking pre-orders for the next batch so I splashed the cash and now have a long wait. It is due mid-February. I hope that there aren't any extra delays!

I will be getting my dumb trainer back in action to keep me going until Victory is mine!

I got a free 2 month subscription to Zwift with my order. I don't know if I can use that now or only after I take delivery. I will email JetBlack to see if I have a choice.

Meanwhile, I will buy a HRM...


That sounds like a good option.

I may also buy speed and cadence sensors to partially 'smarten up' the dumb trainer, though I can't see how they could give an accurate measure of power, given that Zwift would not know what resistance had been selected, what type of tyre was being used, the tyre pressure, or how hard the tyre was being pressed against the roller!

I think you’d probably be best waiting until your smart trainer arrives before you start using Zwift. TBH, if there’s a disconnect between the way that the bike feels and the way that the on-screen terrain is presented, that would really annoy/confuse me. The in-game ‘mileage’ that you do would bear even less relation to riding in real life!

I suspect that you’d also find that it would vastly overinflate your power, and that you might be disappointed/disincentivised when you do progress to using your Victory.

 

[ColinJ]

I think you’d probably be best waiting until your smart trainer arrives before you start using Zwift. TBH, if there’s a disconnect between the way that the bike feels and the way that the on-screen terrain is presented, that would really annoy/confuse me. The in-game ‘mileage’ that you do would bear even less relation to riding in real life!

That is what I was starting to think this afternoon. A HRM will be a worthwhile buy but I don't really feel that buying extra sensors to guesstimate power would be!

I won't have gears on the dumb turbo bike so it would be hard or impossible for me to cope with significant climbing at speed without lowering the resistance on the trainer.

I think I will just ride along to some of the many training videos on YouTube until my Victory arrives.

The most urgent task is to either get my rear wheel sorted out or to buy a replacement. The current wheel is out of true and significantly not round, causing a thump for every wheel rev. The only way to avoid the thump is to lower the tyre pressure and the force against the roller, but then the tyre slips when I try to accelerate. Wheel truing is not my forte so it will be an LBS job!

 

[alex_cycles]

Isn't ZRS, or at least what Zwift are doing, just the old CE system in disguise?

E 0-180 = D riders
D 180-350 = mostly low and mid C riders
C 350-520 = C sandbaggers, low B, mid B
B 520-690 = Upper B and lower A
A 690-100 = remaining A and A+

They could have just seeded everyone using the old CE setup, given all Ds 100, all Cs (excluding the sandbaggers) 200, upper Cs, low Bs, mid Bs 300 etc etc, so new groupings

E = 100
D = 200
C = 300
B = 400
A = 500

Then let results promote/relegate based on results.

Top 10% of a race increase their score - winner 10 points, 2nd 8 points .... not thought the scoring out exactly but wouldn't take long to come up with something reasonable.

Bottom 10% in a race get a minus score equivalent

Middle 80% of riders no score change

If a D reaches 250 points, they are promoted and their score changes to 300 points (stops the yo-yoing each race)

If a D is relegated they set the score to 100

Races with less than 10 riders, no impact on scores

If riders DNF 3 times in any given 3 month period they are penalised with 10 points

Minimum effort could be as they plan, anyone doing it has zero score change (or 5 added to their score)

No degradation of scores, so if a rider with a new C score of 320 goes off for 6 months, they come back to the same score.

Needs more thought, probably enough holes in it to make a good dutch cheese, but works similar to the old CE but should control sandbagging more. Most riders coming mid table stay where they are, which seems logical.

I bet they could have done something similar to this in no time at all - would have met 90% of the racer's needs, would have answered the sandbagging problem that some didn't like in the old system and after the initial groupings, removed power from the methodology and makes it purely results based.

Right, I'm off for lunch whilst you guys rip my logic apart

It's irrelvant now after today's announcement https://forums.zwift.com/t/zwift-racing-score-seed-v2-release-december-2024/640588/461

So the new calcs start at 2000 tonight and we'll all wake up tomorrow with another new score that will not disadvantage lightweight and female riders like V2 did. This is really a HUGE U-turn, but it's the right thing to do. Yesterday's changes had some ridiculous outcomes like 36kg children having >900 seed score.

 

[Whorty]

It's irrelvant now after today's announcement https://forums.zwift.com/t/zwift-racing-score-seed-v2-release-december-2024/640588/461

So the new calcs start at 2000 tonight and we'll all wake up tomorrow with another new score that will not disadvantage lightweight and female riders like V2 did. This is really a HUGE U-turn, but it's the right thing to do. Yesterday's changes had some ridiculous outcomes like 36kg children having >900 seed score.

They are fighting a losing battle. Whatever they do they aren't going to get it right. Too many variables, not least humans who don't behave in a predictable way. It really is becoming a farce now


I expect I'll be back at 400 tomorrow then because I'm a heavier rider who goes to the gym 4 times a week

 

[Whorty]

Also to add, and what I've said before and someone else said on that thread - this scoring mechanism is going to result in a lot of riders (possibly all) yo-yoing around the cat limits; come top half get points. 10 races in 40th out of hundred riders could see someone 'promoted' to the next group up. Get blown away there as they're far too weak for that group, lose a few points, get relegated. Come 40th, get promoted etc etc

Again I wait to be proven wrong, but my track record on this so far has been pretty accurate so I'll not hold my breath (not with asthma anyway, not good for me haha)

Only those winning consistently and too strong for a cat should be promoted, only those too weak and losing consistently should be relegated. Everyone else will be in their correct pen. They may always be towards the back, or towards the front, but that's ok so long as they get a good race and aren't totally outgunned or cruising and sandbagging.

 

[CXRAndy]

I don't know your rear wheel width on your single speed? But if it matches the Wahoo Core with a cassette. You could get the core with 12 months subscription and be riding in a few days.

 

[alex_cycles]

They are fighting a losing battle. Whatever they do they aren't going to get it right. Too many variables, not least humans who don't behave in a predictable way. It really is becoming a farce now


I expect I'll be back at 400 tomorrow then because I'm a heavier rider who goes to the gym 4 times a week

It will be interesting to see. I'm not going to say you're wrong because I simply don't know. I strongly suspect you'll be well under 400.

 

[Supersuperleeds]

Does anyone else just use Zwift for gentle paced rides and not race? I feel like I am in a minority.

Me, I've absolutely no interest in racing. I tend to have a tv programme or film on while on Zwift and just bimble around in Z2

 

[13 rider]

ZRS back to to 353 🤣 , thought this recalculationnwas to help lightweights

 

[Whorty]

ZRS back to to 353 🤣 , thought this recalculationnwas to help lightweights

I'm up to 253 which as a lower mid C racer feels about right (between 180 - 350). Using that logic you should be below 350 so the new seeding definitely hasn't helped you, but maybe you had one ride that would have pushed you into B in the old CE world?

In the old world you needed a 3 ride average to get into B, but the new method only used your best performance so is worse for light riders surely?

Also love how they scrapped the 20 mins as it was totally 'wrong', and went with 10 mins and 30 seconds because that's far superior and fully tested and we know we're right as we have PHD brain boxes on it (V1). After 3 months of shoot-shows, they finally accept that their PHD bods may have got it wrong, so dropped the 30 second power, and that's clearly the best way to reseed (V2). Two days later and no, all previous models were clearly wrong and 5 minute power is obviously the way to go (V3)

The problem I see with 5 minute power is it still allows for sandbagging, probably more so than 20 minutes. In a pack, I might be on my absolute limit hanging on and pushing 3.5 w/kg for 5 mins, but others may be cruising, but to their model we look the same. Those cruising, as we all know in races, are not going to push any harder than they need to so they aren't likely to hit their 5 minute max. We'll see though, but we just seem to have gone to roughly where we were previously on the groupings, but promoted climbers like you who have a good 5 minute climb.

 

[Whorty]

My ZRS is likely to be destroyed this morning - joining the Tinies in E group, which they have set 0 - 260. As a higher valued rider in that group I should be at the pointy end of the races, so could gain a lot over 4 races
Saying that though, not done any Tinies for 2 years so my body and lungs may not cope with the explosive effort (asthma meds are ready as I expect to be having the odd breathing problems!)

Edit: saying that, ride 2 has a KoM finish so I 'll be nowhere near the front for that one!

 

[Norry1]

Just had a look out of interest and my score is 391 - quite a bit higher than it was last time I raced ( a while ago).