Ok, so to kick off another round of PDv4 test events I would like to give a more detailed description of how the system works in order to avoid more guessing and speculation that leads to false information being spread.
For the ones that are not familiar with PDv4, essentially the goal is to improve on the current pack dynamics system to try and fix a long existing issue which is the “automatic” relay of riders at the front of a pack, even without actively putting effort to pull the group, which leads to excessive pack speeds.
How the system works?
The core change behind PDv4 is the application of auto-braking when travelling inside a group in order to reduce automatic forward movement. If for some this sounds strange, the idea is to mimic what also happens inside IRL pelotons where if you are inside a group a lot of times you have to tap the brakes so you don’t crash into the rider(s) in front of you.
Rules for the auto-braking
Auto-braking will be applied if:
- The amount of draft savings exceeds a certain threshold (this threshold is variable according to the gradient. For instance, it is set at 38% for flat. These thresholds are configurable server side, but there is no point in detailing the values given that they are not visible for you in the HUD. Maybe something to improve in the future…)
- AND your speeds exceeds the speed of the bike in front of you
- AND your power drops below your last 10 sec. average power (signalling you are slowing/relaxing).
- AND your power does NOT exceed X% above your last 10 sec. average power (currently X is set at 110%. It can be changed if needed).
So to put it in simple terms, if the system detects you are “relaxing” your power but your speed is above the rider in front in HIGH draft situations, it slows you down.
Other situations:
- If you are travelling at a much higher speed then the rider(s) in front of you, you will never get auto braking. Currently the limit is set at 3km/h (it can be adjusted).
Double Draft
The previous system contained double-draft active by default. This time we decided to turn it off by default in order to have the option to turn it on or off. However, for the first few test events we will be setting double draft ON.
Visual Feedback
One natural complaint from previous tests is the lack of visual feedback. To improve on that we included a visual queue every time auto-braking is being applied when you are inside a pack.
The power number of the top left corner of the HUD will turn red whenever braking is being applied. That way you can decide your actions based on that:
- If your goal is to continue in the group and you see auto-braking perhaps you can just relax more and trust the draft in order to save energy.
- If you see auto-braking but your goal is to be aggressive at that time, perhaps it’s time to accelerate and move up, either to break away or position yourself more to the front, for instance in the last moments of a sprint finish.
This visual feedback can also be easily turned on/off, so if we find that it’s more harmful than good we can easily turn it off.
Other concerns
Is the auto-braking some sort of draft lock?
It’s not. After the last round of events, and from the feedback seen here in the forums there was some concern around this system, like if the auto-braking was some sort of “tight lock”. It’s not, and you will see that with the visual feedback of the red power numbers.
Besides, the previous version contained a bug that made the system much slower to respond causing a bad experience in a lot of situations. Hopefully that will be sorted now.
I’m doing an all out sprint to the finish, maybe I get braked?
If you are in a position where you have mostly a clear road or riders not in a tight group formation, that is almost impossible. Unless you are boxed in a tight group the amount of draft savings won’t be enough to trigger it.
Current limitations
Currently the downhill experience might not yet be the best in terms of the speed reduction we are looking for. We need to test and adjust accordingly based on feedback.
Or, maybe I could be wrong and it’s already good enough 