How To: Quickstop

VESC Bible Tuning and Riding
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I’ve seen a lot of people struggle with Quick Stopping and the technique behind it, so I wanted to share some insight on exactly how it works and how you can pull it off yourself! Please don’t hesitate to ask questions if you have any, or leave some videos of your own looking for feedback.

Before going over technique, I first want to clarify how Quick Stopping is handled in the Float Package, as some may not realize it’s actually a built-in feature! Essentially, under the right conditions, the configured Full Switch Fault Delay is skipped entirely, instantly disengaging the board in order to prevent backwards freespin. Here are those conditions:

  1. The board’s angle (True Pitch) must be beyond 14 degrees from level
  2. ADC1 and ADC2 must be below their respective thresholds (essentially, front foot lifted off sensor completely)
  3. The Motor ERPM must be in the range of 200 to -200 ERPM

Simplified, this means that once the motor comes to a stop, if the tail is near the ground with your front foot lifted off the sensor, it will disengage the board immediately to mitigate backwards free spin.

So, how do you Quickstop? Well first, lets quickly go over a few of the “Don’ts” of Quick Stopping:

  • Do NOT wait until the board is at a complete stop before reacting, the action is much sooner/earlier than you think
  • Do NOT drag your tail to oblivion (I mean, you can, but it’s not practical and can be much less controlled, and just obnoxious)
  • Do NOT slam your tail down with all your weight and force (please, have some mercy on that poor battery)

For Quick Stopping, it’s largely technique, though keep in mind that too stiff of a tune may make it considerably more difficult. But with the right technique, it’s more than possible on the default tune, as well as many of the tunes in the Tune Archive. The lower the brakes allow you to get your tail and the softer the brakes, the better.

A bit of momentum is required. Nothing crazy, you’re just going to need enough momentum so that you can kill some off by braking in order to get your tail down before coming to a stop. At a cruising pace (or more), coast on the brakes in order to get your tail low, hovering just above the ground. You don’t have to drag it, just find that sweet spot right above the ground. Once you’ve slowed down to a pace where you can safely plant your foot and stop your remaining momentum, gently set your tail down (this will be a very short tail drag, so that you can “stand” on your rear foot), and lift your front foot off the pad to plant on the ground.

This action is somewhat quick, but smooth, it should feel natural. One way to picture it, is imagine a curb or stair in front of you, and you’re stepped up onto it with your lead foot. Then just pull your lead foot off and bring it down next to your other foot. That simple. It will also be much sooner than you might anticipate. Don’t wait until the motor is at a complete stop! You can safely plant your foot earlier than you think, maybe somewhere in the 3-5mph range. The sooner the better, as long as you don’t stumble, as this will ensure all conditions for Quickstop are met once the motor comes to a stop, disengaging the board before it can shoot backwards. And lastly, don’t slam the tail down! The smoother the motion, the better. If you quickly jerk the tail down, Rate P will kick in very aggressively, making the board want to shoot off backwards much quicker than if you ease into it.

Final Tips:

Practice makes perfect. It will take some time to get the timing down and get comfortable with the motion, but it truly is one of the most important skills you can unlock early on, and will help you feel much more comfortable with dismounting the board in general. As you get more experienced with the technique, you will be able to perform it at slower and slower speeds as well, as you can throttle the board in front of you to get the tail down instead of relying on pure brakes, at least with the right tune.

Additionally, a little bit of deweighting goes a long way! Giving a small hop before lifting of your front foot can make the motion much smoother, it can mitigate the small amount of tail drag needed without it, and it also helps for Quick Stopping at much slower speeds. If needed, you can even use this technique to dismount in a similar fashion but from a complete stop (Assuming you don’t have an extra long Full/Half Switch Fault Delay)! Just imagine jumping backwards off your board, but leave your rear foot on the rear footpad, only pull back with your front foot. By the time your weight comes back down on the tail, the Switch Fault will have likely kicked in, meaning the board will disengage and the tail will just drop.

Here’s some videos that cover the technique I’ve explained here, in order to help visualize what’s going on (make sure to enable audio). Please feel free to share your own videos if you are having trouble and need some feedback!

Quickstop Demo 1:

Quickstop Demo 2:

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Just like most features in the float app, this should be a toggle able feature. I am not sure why this was included without the option to disable it. Maybe I want to to a tail grind and slide back up to speed going backwards. I can just see many situations where this can trigger. Maybe I slowed down to a complete stop down an incline and I have great tail clearance or w rails that allow my angle to reach -14 degrees. This is a pro rider feature, just like dark ride. Please add the option to turn it off, other than that I like the feature and think it works for what it’s meant to do. But it doesn’t adhere to the general idea of having full customization.

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Both of the situations you described will not trigger Quickstop, as it requires you being completely off the footpad to trigger.

There’s a lot we do that doesnt adhere to the idea of full customization, including many “features” that really aren’t talked about. If we included parameters and toggles for absolutely everything, things would be significantly more overwhelming than they already are. There are many behaviors and features that are permanent and behind the curtain, so to speak, because theres just no real need to customize them. So we really try to limit things where we can when we don’t see a need for users to modify the behavior. Especially when it comes to adding features, as once a feature is added, it’s near impossible to smoothly remove a feature without backlash/discussion even if nobody changes it, because of that desire for full customizability.

It’s a fine line we have to walk, and when it comes to Quickstop specifically, we still havent seen any need to implement a toggle in the year+ that it’s been baked into ATR firmware and the Float Package. Of course we can be open if there are legitimate concerns of cases that would trigger dangerous unintended “false positives” or something along that nature, thats exactly what happened with the Simple Start feature which used to be permanently enabled as well. But as of now, we haven’t seen any need for action like that.

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Once I figure out some compilation errors for qt I plan to get an option in for disabling Quickstop during any amount input tilt rather than just inputs greater than 30deg (at least in a local package for myself) . As much as I love the feature I have had false positives too many times while trailing for me to comfortably keep it enabled as broadly as it is currently. These have all primarily occurred while bonking over roots on uphill sections while giving input tilt.