ElectricMotorcycleForum.com
Makes And Models => Zero Motorcycles Forum | 2013+ => Topic started by: Jarrett on March 22, 2019, 07:57:26 PM
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That is the question.
When thinking about an S or DS, should one consider the SR or DSR is the larger question.
Why or why not?
Has it been discussed before? The search function wasn't helpful with such short words.
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Well no real secrets to discuss, the stats on the bikes' range of models are pretty clear. Once you've test rode them to let your mind wrap around what those torque numbers feel like you know which one is best for you.
The only draw back of an "R" model that I've heard of is an increase in insurance cost. And higher cost of the "R" bike of course.
The bikes ability to switch modes and dial down the top speed and torque values on the app means even a new rider can have a R and just slowly build up to the full power when they're comfortable. Worst case is the buyer never goes full power but the next guy who owns it might want to very much.
I wished they would drop the standard bikes and offer the "R" models listed under the standard S and DS title for the insurance savings.
I don't feel a bike that goes less than 150MPH should be an "R" but that's just my feelings.
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Kinda curious to hear from those that have had both.
Maybe some that went from a DS or S to an R model or vice versa and if it made any difference really.
I know the stats say they all have the same range, but wondering if the R models really deliver the same range in real world use.
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I started on a 2013 DS (26k miles) and moved to a 2016 DSR (39k miles now).
The range/efficiency is absolutely the same if you hold the throttle at the same input. I use an Atlas throttle lock and a crampbuster hand rest to smooth out throttle motions on the DSR to avoid spiking current to the motor, AND to not jerk my passenger around.
When I bought the DSR, the IPM motor was new and I opted for the DSR to get a better-longevity motor. It might also be helpful that the controller and cabling are more robust, in the long term. I like the idea of having equipment rated for more than I need, so the thermal/etc stresses are lower.
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I know the stats say they all have the same range, but wondering if the R models really deliver the same range in real world use.
I would say so, if both used the EXACT same way. No doubt the "R" will have less range when you use the extra power available.
Mine is almost always in the eco mode. I usually stay off the freeways until I must, with my electric bikes. I use my electric bikes mainly for the every day around town stuff and I find they take the place of my cars more so than they do my other bikes. I really have no need for the "R", but the power is there for when I want it, which is very rare.
-Don- Reno, NV
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Well WTF. Do you want to go fast or don't you? It's basically that simple.
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No doubt the "R" will have less range when you use the extra power available.
I hate to be a nitpicker, but it's not QUITE that simple. It is for an ICE, which becomes highly inefficient whenever you press that accelerator pedal hard (or twist the grip hard). But EVs don't; they're still quite efficient even at high throttle openings. Of course, if you accelerate harder, it draws more power, but for a shorter time until you get to your cruising speed. Because of the consistently high efficiency of the electric drivetrain, it really is almost a wash.
Almost the ONLY factors in an EV's range are cruising speed and drag.
Well WTF. Do you want to go fast or don't you? It's basically that simple.
To pick nits again, that's not really the right question. "Do you want the ABILITY to go fast or don't you?" is the right question. Nobody is going to tell you that you have to twist your right wrist. With the faster bikes, you have the option. That's how simple it is.
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But EVs don't; they're still quite efficient even at high throttle openings.
On our Zeros, we get about half the range every time we double the speed. That doesn't sound all that efficient to me at the higher speeds.
That means if you're in a hurry to go a distance, go very slow. You will save more time by riding slow than by having to recharge longer. At least in most cases.
I would say efficiency is more important in an EV than it is with ICE. We are efficient when we ride very slow. Not so much when we're riding fast.
-Don- Reno, NV
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Kinda curious to hear from those that have had both.
Maybe some that went from a DS or S to an R model or vice versa and if it made any difference really.
I know the stats say they all have the same range, but wondering if the R models really deliver the same range in real world use.
I own both. They are sitting side by side in my garage. Get the R if you can afford it. The DSR does everything the DS does and more.
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On our Zeros, we get about half the range every time we double the speed. That doesn't sound all that efficient to me at the higher speeds.
That means if you're in a hurry to go a distance, go very slow. You will save more time by riding slow than by having to recharge longer. At least in most cases.
I would say efficiency is more important in an EV than it is with ICE. We are efficient when we ride very slow. Not so much when we're riding fast.
-Don- Reno, NV
Re-read what I said. Drivetrain efficiency isn't related to aerodynamic and other losses. You can accelerate as hard as you want to up to a 60 mph cruising speed, and you'll still out-range someone babying it up to a 65 mph cruising speed, every single time. Acceleration almost doesn't matter, cruising speed is by far the most important thing. That's why I say you can enjoy the power of the "R" models frequently, every day, and not even impact range or driving costs.
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Re-read what I said. Drivetrain efficiency isn't related to aerodynamic and other losses. You can accelerate as hard as you want to up to a 60 mph cruising speed, and you'll still out-range someone babying it up to a 65 mph cruising speed, every single time. Acceleration almost doesn't matter, cruising speed is by far the most important thing. That's why I say you can enjoy the power of the "R" models frequently, every day, and not even impact range or driving costs.
This has not been my experience at all. 3/10ths pace in Eco mode gives at least twice the range compared to 7/10ths in sport mode. And have you gotten an insurance quote for the SR? $177/month.
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You can accelerate as hard as you want to up to a 60 mph cruising speed, and you'll still out-range someone babying it up to a 65 mph cruising speed, every single time. Acceleration almost doesn't matter, cruising speed is by far the most important thing. That's why I say you can enjoy the power of the "R" models frequently, every day, and not even impact range or driving costs.
Yes and no. If you only accelerate fast a couple of times, yeah, but only because it's only for a few seconds of excessive battery drain. Do it a lot and those seconds add up very fast to reduce the range.
On an electric motors, acceleration drains battery MUCH faster than cursing at a steady speed. It's just that the acceleration usually doesn't last long. Do it a lot and watch your range drop down a lot.
-Don- Reno, NV
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Do it a lot and watch your range drop down a lot.
I've done that. Have you? Many days, on my commute to and from work, I'll accelerate to cruising speed at full throttle. It doesn't affect my state of charge when I'm done in the slightest.
Look, accelerating twice as hard in an ICE vehicle requires much more than twice as much fuel. That's because the efficiency of the ICE drivetrain goes down very fast at higher throttle openings. But accelerating twice as hard on an EV requires almost exactly twice as much current -- for half of the time, since you get up to cruising speed faster. Since the EV maintains its efficiency at high throttle openings, twice the current gives almost twice the acceleration.
If you have a repetitive drive, like a commute, do the experiment. Try accelerating hard some days and much more gently some days, but don't change your cruising speed. Then experiment with the cruising speed instead. You'll find, as I have, that acceleration speed virtually doesn't matter. It's the cruising speed that determines range, almost exclusively.
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If you have a repetitive drive, like a commute, do the experiment. Try accelerating hard some days and much more gently some days, but don't change your cruising speed. Then experiment with the cruising speed instead. You'll find, as I have, that acceleration speed virtually doesn't matter. It's the cruising speed that determines range, almost exclusively.
Your explanation seems plausible to me. I want to try the experiment. But then what does ECO mode actually change? Just regen and max speed?
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If you have a repetitive drive, like a commute, do the experiment. Try accelerating hard some days and much more gently some days, but don't change your cruising speed. Then experiment with the cruising speed instead. You'll find, as I have, that acceleration speed virtually doesn't matter. It's the cruising speed that determines range, almost exclusively.
Your explanation seems plausible to me. I want to try the experiment. But then what does ECO mode actually change? Just regen and max speed?
That and the amount of, torque and power (and therefore acceleration), per degree of throttle rotation.
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That and the amount of, torque and power (and therefore acceleration), per degree of throttle rotation.
I think the speculation is that that should not matter, only cruising speed. E.g., the same number of Wh should be required to go from 0 to 60 whether it's done in 4 seconds or 8 seconds, right? From E=(1/2)mv^2.
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That and the amount of, torque and power (and therefore acceleration), per degree of throttle rotation.
I think the speculation is that that should not matter, only cruising speed. E.g., the same number of Wh should be required to go from 0 to 60 whether it's done in 4 seconds or 8 seconds, right? From E=(1/2)mv^2.
He's saying that the mode (Eco vs Sport) changes the amount of current / torque delivered per physical position of the throttle.
Separately, for a given amount of current / torque delivery, the energy expended to get to cruising speed varies let's say negligibly.
BUT there's a fun factor to throw in:
- For a given amount of current / torque requested from the throttle,
- The battery voltage will sag by a proportional amount because of internal resistance.
- This will then subtly effect the power delivery in the same manner that operating at a lower SoC will.
- This might also be less efficient generally.
It's more or less negligible, but the point is that it helps with battery power delivery efficiency to smooth out or minimize fluctuations in throttle usage.
I've run tests using a live data logger (the third-party mobile app for Android that Apple's policies make unworkable on iOS) to watch current, voltage, etc. on a pretty high sample rate to understand the effect of the throttle on overall electric power delivery.
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BUT there's a fun factor to throw in:
- For a given amount of current / torque requested from the throttle,
- The battery voltage will sag by a proportional amount because of internal resistance.
- This will then subtly effect the power delivery in the same manner that operating at a lower SoC will.
- This might also be less efficient generally.
Yes, it's true that the efficiency of the electric drivetrain suffers SLIGHTLY at higher throttle openings. Also IGBTs, MOSFETs or any power switching device will have slightly higher voltage drop at higher current draw, contributing another little bit to efficiency loss -- not to mention the voltage drop in the wiring itself. But it's nothing like the toilet-flushing effect when you open the throttle on an ICE.
I've run tests using a live data logger (the third-party mobile app for Android that Apple's policies make unworkable on iOS) to watch current, voltage, etc. on a pretty high sample rate to understand the effect of the throttle on overall electric power delivery.
I'd love to see your data. I'm confident I'm correct but it would be very nice to see numbers to prove my point.
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I'm not saying the controller / power switching is less efficient because of the voltage drop. I'm saying that the voltage drops and you need to draw more current to supply the requested amount of power. Any losses I'm mentioning are from internal resistance which heats the battery a bit.
And I agree it's absolutely nothing like what happens with a literal throttle operating an ICE powertrain. The largest battery one can equip on a Zero is 18kWh max / 15.8 kWh usable which is equivalent to a half gallon of gasoline, and we're basically hypermiling out of that with almost all the losses due to drag, then rolling resistance, and then finally internal inefficiencies.
I'm not sure that the data dumped will be very useful, unfortunately, since throttle position isn't recorded. But I do know how much voltage droops depending on the output current. It's substantial enough that I can see why the dash doesn't show it - our skittish owner population would freak out.