ElectricMotorcycleForum.com

  • April 25, 2024, 07:08:08 AM
  • Welcome, Guest
Please login or register.

Login with username, password and session length
Advanced search  

News:

Electric Motorcycle Forum is live!

Pages: [1]

Author Topic: Math behind Custom mode settings?  (Read 557 times)

Crissa

  • Hero Member
  • *****
  • Posts: 3144
  • Centauress
    • View Profile
Math behind Custom mode settings?
« on: December 15, 2019, 06:59:41 AM »

Does anyone know how much the Custom torque settings modify actual torque or horsepower?

Like, full power on my S is 0.24KW/kg but I've never set it to that nor do I expect to get that in real-world output.  But in 50% setting exactly half that?

-Crissa
Logged
2014 Zero S ZF8.5

TheRan

  • Hero Member
  • *****
  • Posts: 1471
    • View Profile
Re: Math behind Custom mode settings?
« Reply #1 on: December 16, 2019, 12:39:03 AM »

I could be wrong but I was under the impression that power output is unchanged and it's just the torque that you can adjust, and I would assume that 50% means 50% so 54.5 Nm. You could check it using the app as that gives you actual numbers instead of the bar graph on the dash, although it's probably best to use a screen recording app to get the max values instead of watching the screen.
Logged

Crissa

  • Hero Member
  • *****
  • Posts: 3144
  • Centauress
    • View Profile
Re: Math behind Custom mode settings?
« Reply #2 on: December 17, 2019, 12:03:49 AM »

You could check it using the app as that gives you actual numbers instead of the bar graph on the dash, although it's probably best to use a screen recording app to get the max values instead of watching the screen.
How would I do that?  Is that in the unofficial zeromanual or thread somewhere?

-Crissa
Logged
2014 Zero S ZF8.5

TheRan

  • Hero Member
  • *****
  • Posts: 1471
    • View Profile
Re: Math behind Custom mode settings?
« Reply #3 on: December 17, 2019, 04:22:25 AM »

You could check it using the app as that gives you actual numbers instead of the bar graph on the dash, although it's probably best to use a screen recording app to get the max values instead of watching the screen.
How would I do that?  Is that in the unofficial zeromanual or thread somewhere?

-Crissa
Do you mean seeing the data in the app, or recording the screen? The app should switch to the ride screen as soon as you start moving but if it doesn't go to the ride screen setup area and then press preview. For recording the screen there are plenty of apps in the Play Store but I haven't tried any of them to make any recommendations.
Logged

BrianTRice@gmail.com

  • Unofficial Zero Manual Editor
  • Hero Member
  • *****
  • Posts: 4014
  • Nerdy Adventurer
    • View Profile
    • Personal site
Re: Math behind Custom mode settings?
« Reply #4 on: December 17, 2019, 04:49:17 AM »

The throttle position is not logged (outside of the motor controller, perhaps, and by intercepting CANbus messages), so there's no *known* way to analyze the correlation between throttle position and outputs like torque and power. Torque is more or less proportional to current, and power is current times terminal voltage (which droops under load significantly, so it's a little trickier).

What the torque setting adjusts is the rate of torque demand increase per throttle position change, as a percentage of the maximum configurable rate. It changes the slope of torque demand and therefore changes how much torque a fully-twisted throttle demands by extension.

Basically, it's an ergonomic change, more about the rider than the equipment.
Logged
Current: 2020 DSR, 2012 Suzuki V-Strom
Former: 2016 DSR, 2013 DS

TheRan

  • Hero Member
  • *****
  • Posts: 1471
    • View Profile
Re: Math behind Custom mode settings?
« Reply #5 on: December 17, 2019, 05:12:38 AM »

The throttle position is not logged (outside of the motor controller, perhaps, and by intercepting CANbus messages), so there's no *known* way to analyze the correlation between throttle position and outputs like torque and power. Torque is more or less proportional to current, and power is current times terminal voltage (which droops under load significantly, so it's a little trickier).

What the torque setting adjusts is the rate of torque demand increase per throttle position change, as a percentage of the maximum configurable rate. It changes the slope of torque demand and therefore changes how much torque a fully-twisted throttle demands by extension.

Basically, it's an ergonomic change, more about the rider than the equipment.
I was wondering how it actually limited the torque so thanks for chiming in on that. So basically, a certain percentage of throttle application equates to a certain amount of torque (so a halfway open throttle would be 50% torque) and limiting the torque changes where on that range the percentage falls i.e. a 50% torque limit would mean that a halfway throttle position would actually equate to 25% of the maximum torque the motor is capable of (and WOT being 50%, quarter throttle 12.5%, etc.).

Makes me wonder how easy it is to adapt for those people that regularly switch between say eco mode and sport mode, getting used to sport mode putting out over double the torque with the same throttle application. It's quite different to an ICE when you think about it, where torque and power are a function of engine speed and the throttle essentially controls how fast that engine speed rises (and the end point of course).
Logged

Crissa

  • Hero Member
  • *****
  • Posts: 3144
  • Centauress
    • View Profile
Re: Math behind Custom mode settings?
« Reply #6 on: December 20, 2019, 03:15:04 PM »

Is it?  Torque availability changes on a standard with RPM and gear and clutch position.

And CVTs and other modern cars vary the reactivity of the motor to the pedal position, speed, and mode setting (like traction control and towing control) as well.

But my question was more about how much this modifies the actual motor output... Is it more or less like a smaller engined bike or just making the throttle lazy?  And is that the difference between a 600cc bike and a 250cc bike?

-Crissa
« Last Edit: December 23, 2019, 03:43:10 AM by Crissa »
Logged
2014 Zero S ZF8.5

TheRan

  • Hero Member
  • *****
  • Posts: 1471
    • View Profile
Re: Math behind Custom mode settings?
« Reply #7 on: December 21, 2019, 12:34:44 AM »

It makes it ride as if the extra torque just didn't exist, so yeah I guess you could compare it to having a smaller engine. As I understand it there's no ramping up to the throttle so you could go from say 25% to 75% throttle and you'd go practically instantly from 25% to 75% torque, the only limit being the available power needed to achieve that torque (and that's why it doesn't limit the power). Even if you set it to something like 10% torque the throttle wouldn't feel lazy because you could go WOT and instantly get that 10%, although the bike itself would feel lazy because it would take longer to accelerate with such little torque. If the limit is instead set at a level where you don't need to go WOT to accelerate at a decent pace then it's going to feel like the throttle is more precise, I suppose a good analogy would be going from a 1/4 turn quick action throttle to a regular throttle.
Logged
Pages: [1]