Is W/kg a good metric for group rides?

I’m a new zwifter. A few days ago, I registered in a group ride which I thought would be fun, based on W/kg metric (that fits my level). I joined the event and then tried to follow my W/kg pace rider. I quickly realized that the group was riding at a much faster speed that I thought it would. I’ve never been able to keep up with the group.
So my question is this : Why using a metric that seem to have little to do with the speed (pace) that you are going to be able to keep, and thus follow other riders.

You ask a very good question. Speed would be a much more useful metric on most routes.

On the contrary I think W/kg works pretty well if the leader sticks to it (which is not always the case). Riders who are on the light side will have to learn to make a mental adjustment as they need to ride at a slightly higher power, but thats easy enough to do.


That’s the thing though, newer riders won’t realise that it depends on weight, and some leaders also won’t adjust themselves if they’re heavier than average. It often leads to a bad experience, never mind the issue of people ignoring the designated pace.

Hi @Jean-Marc_Leclerc

The ride that you picked is the w/kg in your blue zone?

From Jean-Marc, we don’t have enough information. It sounds like he’s saying he was riding at the w/kg that the ride was listed at, but couldn’t keep up. If it’s a weight thing, then was ride leader heavy, and he is light, and that’s the cause?

Before joining a ride, I’m not aware of an existing database of ride-leader weights that we can reference to know in advance how we’d need to adjust our output.

I don’t think the ride leader’s weight matters so much, it’s the participant joining them.

Agree there‘s a learning curve. There’s a learning curve for just staying in the draft too. I had a couple of disappointing experiences in my first few group rides. A better onboarding experience for newbies would be welcome.


Yes John, that’s what I was saying.
My point is that a rider (preferred) average speed, for example, would be a better metric for grouping purposes than w/kg. In many instances, I noticed that riders with similar w/kg finish way ahead of me, they ride at a higher speed.

Hi @Jean-Marc_Leclerc

What event was this? What is your weight?

As James said the ride leader’s weight does not make that much of a difference.

Well, yes and no for average speed.

Yes, it can be helpful if provided as additional info in a ride’s description. There are a lot of recurring rides that have the same leaders week in and week out, sometimes over the same course. A lot of these courses have been ridden before by other riders and having an avg speed listed would make a lot of sense in my opinion.

No, it wouldn’t really be too helpful if you’ve never ridden the course before, and/or never in a draft on that course, as you wouldn’t have a point of reference to know how you’d do.

Why does this continue to be said? A 2wkg ride, if led by a 60 vs 90kg leader will change in speed by about 2.5mph and for the actual watts, differ by 60 watts.


Average speed on a route that are not flat will also not work.

Best is to pick a group ride that will put you in the blue zone, then if it are a bit faster you will be top blue or bottom green. The problem is people pick rides that are to hard for them. Thake your (FTP x 0.65)/ weight (kg) that should be the group you ride in.


Closer to 2km/h on a perfectly flat road. Once the road go to 3% then it is 1km/h

This is why I said you need to pic a event that is in your Blue zone if the leader is on the extreme end of the spectrum then you can keep up.

Speed will not work - neither is it a good way to gauge effort, nor can it be easily controlled. Been there, tried that six years ago.

However, all group rides (as mine do) should have in their description the expected pace both in W/Kg and absolute power. Lighter and heavier riders can then better assess what to expect. Rides should also clarify whether the leader will adhere to the pace limits or whether it is an average (where you can expect surges, chases, and other large variations in pace).


Can you explain why? Remember we’re not talking about races, but rides. ZHR aside from the Audax(?) doesn’t seem to run too many rides? The Audax wouldn’t be a good example either, as the range listed for eg. an E ride is 1-3.2 wkg.

Sometimes an example works. Eg. there’s a HERD “Rode to Recovery” ride. Every week over well-known oft-used routes (Tempus Fugit, etc). Is it really difficult to come close on avg speed for the hour (especially since the organizers are able to look back at months(?) worth of historical data and averages)? Why does it work very well IRL across bike clubs all across the US?

Also, make sure you have not selected a TT bike or gravel or MTB (MTB is best if the group ride is on the Jungle loop) otherwise a road bike is best for drafting.

About 164 pounds or 74 kg
I use to ride between 2.0 and 2,5 w/kg (easy).
In that event, I registered in the D cat and like I said, never been able to keep up with the pace leader.
Event : Black Cyclists Network Group, cat D 1 to 2.5 w/kg

Another somewhat confusing ride listing. Shown as a 1-2.5wkg ride, and part of description is “we will ride at 2.5wkg and below pace…” As you might guess, the average watts shown in zwiftpower cover a large range.

Was this the event?


The ride leader is about your weight.

It look like he kept it to 2.5w/kg and under for most of the ride and spiced it up in the last 20 min.

Why? it mean 2.5w/kg and less. Therefore if you cant ride at 2.5 you will be fine.

Yes there was a “little competitive PURGE at the end” therefore people went all out.