Anti sandbagging and other areas that need development and communication

And no wonder, @Tim_White . But Zwift’s take on this is that racing appeals only to a small number. (A number that is sometimes thrown out there but which I don’t believe btw - show me the data!) So all is as it should and they’re in the right not to pay attention to racing but rather to all these minor cosmetic glitches in their patches. They really don’t get it.

Racing is integral to (outdoor) cycling. Even if you don’t race yourself, it’s still there. Everyone knows it. It’s why they are in cycling in the first place and why they buy a bike looking the way it does. They wouldn’t if there wasn’t racing in cycling.

It’s there in running too. It is VERY common among runners to participate in at least the occasional organized timed event. They don’t participate to win because 99.999% can’t win a marathon or shorter event, but they still participate. Why? What would be the point? We know why.

It’s really no different from football. You can play at a picnic with friends or play with your kids. It’s just for fun, but you wouldn’t play at all if it wasn’t for the competitive element (however friendly you make it for your kids) and for the fact that football IS competition.

Cycling isn’t yoga. And even yoga is competitive but maybe for the wrong reasons. Ask any 30-something urban woman who frequents a yoga gym.

So if racing doesn’t appeal to everyone in Zwift, then you are under obligation to ask yourself why. Do people simply not want to be exposed to competition even if grouped with people of very similar ability and all in good fun? Or is there any chance that a sizeable share of those who don’t want to race, especially among those who tried once, don’t want to race because Zwift races suck? That they don’t want to be humiliated, exploited, maltreated? By Zwift?

Because the fault was NEVER with the sandbaggers et al. “Every society gets the criminal it deserves” (wrongly attributed to Rober Kennedy). You create cheaters in Zwift. We know nothing of the motives or personalities of cheaters in Zwift. All we know is Zwift made them happen and has continued to do so in spite of our protests for years.


The quick fix is to give race organiser the “Race Pass” facility, you can invite teams and they control their riders, if they don’t you can speak directly to the team Admin, warn once then remove the whole team, make it very public so other teams are aware. It does mean that all riders would have to be in a team but you could also have a few “ZHQ Open” races, so the rest can still race. It does work, it is also very easy to run “split” Cat’s as you have more control over the riders.

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First post so please don’t shoot me down in flames…

I totally get the frustrations expressed about this, and in the month or so I’ve been using Zwift I’ve fallen foul of it a couple of times. On both occasions I’ve been DQ’d for going over the WPK on ZwiftPower (no complaints by the way, totally deserved it.)

However the issue I’m presented with is that while I’m apparently too strong for the C Cat races, the first time I was DQ’d in a crit, I finished about 9th (I think) and to be honest I was hanging on by the end so it’s not as if I rode away from everyone and found it easy. I suspect I’m not the only one who’s had this experience.

Moving up to the B category I’ve had an absolute hiding so far, and I’m talking about being dropped in the first mile or so, riding alone and finishing minutes behind, even in the shorter races. To be honest far less fun.

While I’ve read through the thread and can see some of the suggested improvements well thought through and well articulated, I do like the approach that the Evo races take, which is to automatically upgrade people who are over category to the next one in the results on ZwiftPower. This resulted in me having an enjoyable race (again, hanging in and not getting dropped) while also not affecting the overall results for the category. Surely Zwift could incorporate this in the main app results without too much difficulty?

Just a thought.

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The problem with retrospectively fixing results like this is that strong riders will still quite likely screw up the race for those who belong in the category. Obviously not the case for you in your specific example. OTOH with a results-based system you wouldn’t be upgraded until you started to win (or at least, finish closer to the front).

I will hazard a wild guess that you are on the light side. Being heavier than average, I didn’t have such a rough time of it. I’m actually offended more by the absurd stupidity of the system than any particularly bad effects on my own racing. Disqualifying people for trying too hard and still losing! It’s insane.


@Adam_O_Loughlin_SAS , I’m guessing you’re fairly light and that this is the reason you got DQ’d in that crit. It goes for any race really but this “feature” of the W/kg cat system is particularly pronounced in the crits.

Like I wrote further up in this thread, you can’t really win a crit as a light rider since even with ruthless wheel sucking you have to produce such high Watts to keep up with the heavies’ naturally higher Watts (because of their bigger muscle mass and since crits are mainly about keeping momentum) that you get DQ’d if you are able to follow them at all and actually try.

The heavies’ Watts stay basically the same race after race so they keep winning and winning and winning without getting upgraded from cat C, since it’s not winning races that upgrades you in Zwift but only increases in Newtonian measures. And in the meantime guys like you pass through C without ever seeing a podium only to get slaughtered in B. The Light Rider’s Curse…

And then these heavies try to comfort you by saying that you’ll get your chance to get back at them in a climbing race instead. They probably mean it, because they believe it. But it’s a fallacy because you are both at the upper end of cat C, meaning you and them can keep a near 3.2 W/kg in a longer climb and then you will be going at the same speed (this is largely true - there is a very very small speed advantage for the lighter rider due to a combination of the gravity element, the air resistance element and the rolling resistance element). So while their weight advantage disappears in a climb, they sure still aren’t disadvantaged. And they still crush you on the flat sections of Lutscher, Greater London Loop etc.

The weight advantage is there in all cats except A since it has no performance ceiling that can get you DQ’d, so you only stand to gain in A to lose weight and you don’t get punished so much for being naturally light. But in B-D weight matters. It is most extreme in cat D. You typically see people around 100 kg on the crit podium. In cat C the average weight is somewhat lower but as long as you can perform at the upper end of the W/kg band you are still advantaged by a relatively heavier weight, so the average weight of the crit podium is still higher than the average weight of the other participants regardless of how you slice them. In cat B the average weight is lower still but the weight advantage persists. And it’s all because of W/kg cats and the performance limit that can get you DQ’d. But this is on ZP.

If you would look at ZHQ results instead you have all the sandbaggers in any race and a sandbagger can be any weight really even though high muscle volume is still rewarded on the flat (and most races are mostly flat), so even if I haven’t made similar calculations on ZHQ results as I have on ZP results, I expect there to still be a tendency for heavy weight dominance but not nearly as large as on ZP.

The weight thing is just one of many strong reasons why some of us in here (or have we grown to many by now?) are fierce advocates of a results-based categorization since it would mean burying the W/kg cats deep and never looking back. W/kg is not fit to be a categorization in virtual bike racing or in fact in any sport. Performance measures as grounds for categorization/divisionalization would kill the spirit of sport in any sport. No wonder no one else [sic!] uses W/kg or some other Newtonian measure to decide who goes where in competitions.

I think Zwift should urgently implement full cat enforcement (as a first step). But your suggestion has some merit in that it would be comparatively very easy to implement since it would all be done within the ZP system, which is likely still totally separated from the ZHQ game engine. Just a web page and behind it a database pulling data from ZHQ. Still not much integration. Easy coding. The problem with the approach, however, is that fewer and fewer bother to sign up with ZP and this is reflected in races as well. Many unregistered participants in any race that these auto upgrades wouldn’t touch. Far more unregistered than just a year ago.

Before corona we used to see this regurgitated standard forum reply daily: “Duuuuude! U can’t look at the ZHQ results. U gotta look at ZP. They are the REAL results. What, are u not registered? Duuuude! U have to register on ZP LOL” (Winning a race that you didn’t actually win, how fun is that?) But you don’t hear it much anymore. It’s probably due to the influx of corona zwifters many of whom have no idea ZP exists. And who don’t care, because why should they when racing works as badly as it does with or without ZP anyway?

ZP was an accomplice in creating the W/kg cats that ruined Zwift racing already early on, so the community is to blame too, not just Zwift. When ZHQ appropriated ZP I hoped that ZHQ had finally come to their senses and that their intent was to destroy ZP in order to replace it with something better, something reasonable. That they would finally take full responsibility over their product instead of leaving it all up to the community. But they didn’t. They never fail to disappoint when it comes to racing.


Actually, there is still a slight speed advantage for the heavier rider as the bicycle weight needs to be added. As the bike weight is constant it is more of a penalty for the lighter rider. For a 3.2w/kg 60kg rider an 8kg bike means their effective w/kg after adding the bike weight is 2.82 while for a 3.2w/kg 80kg rider their effective w/kg is 2.91w/kg.

Zwift Insider has done the testing on this and proven that heavier beats lighter in every situation.


So whatever happened with all the testing they did for the ZRL classics? Are they rolling it out to ZRL season 4?

No, and I don’t think that was ever the plan anyway due to the team format - can’t really have dynamic pens.


Any update on category enforcement for existing categories? Potentially the tools for existing race organisers to toggle on and off, rather than Zwift itself offending precious customers who want to sandbag?
@xflintx ?


I think Flint & Shooj are on holiday. Must be due back soon….

Heavy people do not get an unfair advantage on zwift. You need to stop with that fallacy. Let’s have a look at all the race results from events with any climbs in!! IRL, heavier people tend to win crits so it’s a pretty fair representation.

(Waits for the 45 paragraph diatribe telling me I’m wrong)


The unfairness is due to the cat system that pits an 80kg 319W rider like myself against a 65kg 259W rider (ie both at top of B cat). I’m faster due to physics, fair enough, but the 65kg guy gets disqualified if he pedals a little bit harder, which is entirely due to Zwift’s stupid categories. That’s why heavy guys have an advantage, they race in lower categories relative to their actual racing performance.

I’m putting it a bit simplistically of course. But that’s the general gist. When I first started zwifting I encountered a handful of 90+kg guys who thought they were “really good zwifters” because they were cruising at the front of C cat races at 300W…while lighter riders were going over limit and upgrading just through hanging in the pack. Insane system.


Yes, here comes the diatribe, and you earned it because you are fact resistant. Yes, let’s look at race results. Let’s look at actual data. And let’s do some real calculations instead of just guessing. OK?

That heavy riders are advantaged is not opinion. It is a fact grounded in scientific method. You, everyone else and his mother who in the past have claimed heavy riders are not advantaged are just expressing groundless opinion with absolutely no backing whatsoever. You never bothered to actually look at data. Neither did Zwift, or if they did they simply didn’t care.

-I have sampled large numbers of races, races where climbs were not excluded (some of the races sampled are e.g. Road to Sky).

-Statistical tests show that on average podium takers are heavier than the rest of the field.

-This difference is HIGHLY (like… REALLY) statistically significant, meaning it is EXTREMELY unlikely that the difference is random.

-This difference exists in all categories B-D although average weights differ between cats (probably because weight variance is lower in higher cats, so the difference might still be proportional - I haven’t checked that part thouroughly yet). The difference is largest in D and smallest in B but still exists in B.

-This difference does not exist in cat A. The reason is not that the riders are somehow fundamentally different in A. It is because there is no forbidden performance ceiling in A that can get you DQ’d. This means a lighter rider is allowed to compensate the heavier rider’s higher Watts with a higher W/kg to compete without getting DQ’d.

-Heavy riders are not really advantaged in climbs, but if you don’t already understand why they are still not disadvantaged in climbs, then you obviously still don’t understand how W/kg cats change Zwift racing compared to IRL racing with its results-based categorization.

I have covered all the above points in this post. You should read it thouroughly. Twice.

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No, it’s not. It’s not scientific.

I did the same and your claims are incorrect. Lighter riders significantly over index on podium places on climbing races. Podium places in flat races correlate with average power, there is some correlation with weight. HOWEVER, heavier people are powerful naturally… they have to carry more weight around, as such, develop more power in order to do so. Its simply conditioning.

This in also untrue… you speak of studies… zwiftpower covered this extensively. W/kg is more important on climbs and a heavier rider has to put out A LOT more power to keep up with lighter riders.

You speak of “scientific methods” but sadly, yours are flawed… you look for the conclusion you want and carry out the ‘study’ under a bias.

Just accept the fact that you need to improve yourself to keep up with people instead of suggesting that it’s the system that’s wrong.

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Or in more simple terms - the categories are determined based on w/kg, races are not (unless you are doing Road to Sky or maybe Innsbruck).

The system is wrong. You are the first person I’ve heard to suggest it isn’t. Zwift know it is wrong, the community know it is wrong, hence the 1000 messages on this thread and even more on the last one.


I didn’t suggest the system wasn’t wrong, interesting that you want to put words in my mouth.

My suggestion was that, on occasion, one needs to look at themselves a bit closer.

I want to see your data and your method.

In my blog post I have at least described method and sample sizes. I am convinced that I can replicate the results. And now I’m tempted to.

I will also go through the below, the “theory”, again for the umpteenth time:

Outdoors the lighter rider has an advantage in climbs. It is not as large as one would think and there are studies that show this. (I can’t quote references from memory but I can look it up and come back if you like.) Rather, the studies say, climbers excel at climbing through a combination of relatively low weight AND high VO2Max AND high recovery rate (they need all three). They deliberately and sadistically kill other riders uphill, that’s their only available game. TT pace uphill alone simply does not give enough advantage against the heavies. But yes, there is an advantage for lighter riders on average. Outdoors.

So why isn’t there an advantage in Zwift too? In general terms, outside of Zwift races, maybe there is. There should be, seeing as Zwift seems to use the “standard” model (there isn’t just one but probably something like this).

But then comes the W/kg cat system and destroys everything we thought we knew about cycling. In races you can’t take just any two cyclists and compare. You need to add the racing context. You need to look at the competitive end of each category, the podium takers, because nobody else will ever matter in the races.

What do they look like, the contenders? In Zwift they come in all shapes and sizes but they have exactly one thing in common. They can all produce a W/kg at or near the upper limit of their cat. (Actually, many of them can do better still - many are cruisers or at least have a small cruise potential they can utilize.)

So let’s take two cat C riders as an example, two contenders. They can both do 3.2 W/kg, on the flat and in a climb. If they couldn’t, then they wouldn’t be contenders. Someone else would who could would take the podium instead. They also can’t do more than 3.2 W/kg. Well, maybe they could when freeriding, but they can’t do that here or they would get a DQ. So they will both stay at 3.2 W/kg.

We also assume that they are both smart and experienced racers. They know to draft when possible and they can do it well. And now they are both participants in a race on Road to Sky.

Now, on the flat you say there is “some correlation” with weight on the flat. This is ridiculous. Any light participant in any group ride led by a heavy ride leader can attest to that. There is just not “some correlation”. There is a clear speed difference at the same W/kg and this I also shows in my trials. In group rides the leader is almost always in draft and the light participant will have to produce noticeably higher W/kg than the leader to keep up. Races are no different.

But what if the heavier racer is already at the 3.2 W/kg limit and in draft on the flat? Then the lighter rider will have to go above 3.2 W/kg to stay with him. But he is not allowed to! So how can he win in a theoretical super flat race with no changes in pace? He can’t, not without getting DQ’d. This has absolutely nothing to do with the physiology of the riders. This is all about the artificial W/kg rule set.

So on Road to Sky the heavier rider has an advantage in the approach. It can go either way. Either the heavier rider can hang with some sandbaggers while still not going over W/kg limits (the lighter rider couldn’t), so that he gets a head start in the climb, or he sits in the same group as the lighter rider but exerts less effort and is fresher when the climb starts.

But let’s forget about the approach. Let’s assume both start the race at the foot of AdZ, both equally fresh, both contenders in the sense that they can both keep 3.2 W/kg uphill, only with different weights. Now what will happen? Well… they will both start climbing at 3.2 W/kg. And keep at it. The heavier rider is faster at that effort on the flat, but what about at an 8% gradient?

They will be going at the same speed!

Well, to be correct, if you look at cycling models/Newtonian physics and only take the riders in isolation into consideration, the lighter rider will have an ever so small speed advantage (we’re talking less than a tenth of a kph). A minuscule speed advantage more than offset in the approach. But as @Aoi_Niigaki pointed out recently, you also have to add bike weight to the equation, which ruins everything for the lighter rider who has to carry a relatively higher bike weight compared to his body weight and Watts than the heavier rider. So the advantage is nullified. This is not opinion. This is physics. Don’t argue with me. Argue with Newton.

This is not to say that the heavier riders has a clear advantage uphill. He doesn’t. Both will climb at roughly the same speed. But the heavy rider is not disadvantaged.

So all in all the heavy riders who are contenders, who are actually in any position at all to win a race, are advantaged on the flat and not disadvantaged in climbs. The light contenders have no advantages at all. The only way to compete against heavier opposition is to produce higher W/kg, but if a light rider is already at the 3.2 W/kg limit then he is not allowed to because of an idiotic cat system that should never have existed. Who do you think comes out on top in races? It’s a nobrainer. It really is. Only people seem to have such a hard time grasping this.


Your analysis is not scientific proof that heavier riders have an advantage. It’s evidence that they achieve better results - but without addressesing possible cause (such as since we aren’t professional the are a lot more very fit but not lightweight riders). So please stow your sarcasm and rudeness


You need to rephrase it: it is not Zwift that is unfair. It is the category system.

In a open race you will see a normal distribution where lighter riders win and heavy riders will be last.


For someone who writes a lot and mentions facts rather to often, there are some glaring omissions/inaccuracies in that…

There are light weight riders winning plenty of racers in B & C.
Cat C are not contained to 3.2wkg - There are cat C riders with 4wkg 20min efforts - my partner is one of them.
There are B riders with 4.5wkg or higher 20min efforts.

The last 2 win or place in pretty much all of their races.

Rather than saying fact, many races are on flat courses, these favour heavier riders, but there are many instances of lighter riders winning.

When mountain courses are used, those who are super light have an advantage due to the watts threshold required within the upgrade path.

The answer as always is more nuanced that shouting facts and long long long posts repeating the same thing.