Zwift speed seems slow and draft issue

I rode stage 2 of the tour de zwift this morning. Average power was 250watts. Last time I rid the stage power av was 200watts. Speed difference between the 2 rides is only 0.5km/h faster today. I’m about 3kg heavier today than the first ride but surely I should have been quicker? What could cause this? Poor Internet connection?
Also every power up I get is 10xp and I don’t seem to be getting any draft as far as I can tell amd it never tells me the distance behind the pack or to catch up etc like it used too. Are all these things a glitch and related? How do I correct them?

Are you riding a TT or Tri bike?

Those don’t benefit from the draft (since they are more aero) and also don’t get the other power ups besides XP.

As to speed, were you on exactly the same bike and course both times?


Yeah Im on a TT bike and didn’t know that about the draft and boost.
I’ll have used a road bike the first time. The lack of draft also explains the speed difference? No point of using a TT bike.

Yeah, get off that tt bike for group rides. The draft effect is huge on those big rides. the power ups aren’t as big a deal if you aren’t racing (IMO), but they do help.

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Yep, no draft on a TT bike. Also it’s w/kg that matters in zwift rather than total power, even on the flat (probably not that significant a difference, and depends whether you’ve updated in zwift too!).

Unless you are doing a TT, which I believe it’s required. And if you are riding solo on flat courses, I would suppose it is faster.

Yes, probably should clarify…
Events/ Races/ Pace Partners - road bike.
When doing TrainerRoad and just sending power to Zwift/ TT’s - TT bike

Unfortunately I do not believe this is correct. Zwift insists on using w/kg for categories, but speed in flat and rolling races still seems to be governed by raw power to me.

I have a junior racer and his w/kg is respectable, but he gets dropped easy. I also get smashed in races by guys at lower or comparable w/kg but much higher power.

Only time either of us are competitive is in climbs.

Exactly, that article agrees with observation (and physics, as zwift should aim to do).

This is another good article about Zwift drafts.


Yes, zwift tries to replicate reality with their physics, so on a flat, raw watts tend to matter more, though weight will add a slight amount of drag from increased frontal area.

On the other hand, you hit the hills, and it basically becomes all about power to weight for climbing.

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It is demoralizing to be ridden off the wheels holding similar w/kg as other riders in races. I don’t race a lot, but the times I did I was dropped every time by the top group of B riders. My w/KG cat is right at the threshold between A and B.

Only thing I can do to be competitive is enter climbing races or just resolve to getting dropped in flatter races.

Yes, that is all part of the classification discussion WRT racing in particular, but also relevant to group rides. W/kg is far from the best and only way to set classes.

For sure. But it is also what would’ve happened in the “real world”, as the drag force increases with the velocity squared and is the dominant force at higher speeds.

I have enough experience riding with really high FTP guys to know that it is much much easier to get dropped in zwift than in the real world.

My guess would be it is because the group dynamics don’t play out the same more than the physics engine of transferring power to rider speed. Group dynamics are much harder to replicate in a computer environment. Real world you have a better sense of how to sit in a draft, and in zwift there is no penalty for bumping into other riders. That makes the group way more chaotic in zwift.

That article explains things I’ve observed - the draft is wacky in zwift.