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[togo]

My SR will definitely spin the rear tire in the dry if I'm not careful coming out of a turn. I have learned after spinning up several times to take it easy if I'm leaned over at all.

After having spilled myself into a busy intersection on a damp day and having fishtailed a couple of times, and having even lifted the front wheel cresting a hill a couple of times, I am now more judicious with the use of the full open throttle on my 2014 SR.  My Custom is now programmed to 85%, which keeps me safer and still gives me plenty of smile.

[laramie LC4]

This may not be the place for my rant but I wouldn't talk any friend I know into owning a streetbike without buying a dirt bike and getting good riding one.  Teaches so many important control skills only encountered on the public road under adverse conditions. When loss of traction, gaining of traction, low speed and high speed "curveballs" are the norm and your reactions are trained to handle them without thinking, all of that transfers to your ability to ride safe on public roads where the obstacles are 200hp,3000lb rubber wheeled boulders rolling next to you ready to smash you.

I have encountered wheelspin without planning on it on the zero but nothing I wouldn't expect the bike capable of, or anything unmanageable.

bravo, well said. like i'm looking in the mirror. learn in the dirt, even in AZ i'd rather hit a cacti than a car. 

Despite peoples thoughts that power is somehow limited in the controller for a less violent launch and more power can be somehow programmed, this isn't true.  The power ramps up because of torque times RPM, and the torque doesn't drop off until about 4000 rpm so the bike will make more power the faster the motor turns up to that point.   Then if torque drops faster than RPM's increase, then power will drop off.  But there aren't any aftermarket programmable configurations to get more power at a lower rpm in the controller through electronic settings.

thank you. now i got the wheelies.... 

laters,

laramie 

[ChainGun]

Electric Terry, thanks for your input. I think the combination of sitting little too much towards the front of the bike, keeping the tires (especially the rear) fully inflated per the manual and miniature bumps in the road caused my read wheel to lose traction. I'll try to lose a little air and position my ass closer the rear part of the bike and see how it feels.

[nigezero]

I reckon Zeros can easily handle grippier tyres. No engine pulse and smooth torque is kinder on them, so you can go soft and still get good life.

[MrDude_1]

It's all about the gearing. One of the great things about electric motors is that they have maximum torque at 0 rpm, as opposed to an ICE, which literally can't even run at 0 rpm. That's one of the big reasons our bikes feel so incredibly responsive, and so much fun to ride. It also makes it possible to use a fixed-gear drivetrain, which literally no ICE vehicle does. That eliminates the gearbox, which is heavy, expensive, requires service, and takes up space on the bike. Eliminating the gearbox is a good thing, but it does reduce the ultimate performance of the machine somewhat.

Think about it...how much performance could you expect out of a Hyabusa if all it had was fourth gear? Your top speed would be reduced, and the performance off the line would be uninspiring at best and require a lot of clutch slipping to do it at all. But the amazing torque of our electric powerplants make the performance off the line surprisingly good, even considering they only have a single, fairly tall gear to give decent top speed. ICEs just can't do that.

This is a very EV biased comment, so Im going to break down the parts I disagree with and explain why I think they are a horrible (but common) way to compare an EV to a ICE vehicle that leads to poor examples and performance. This isnt personal agenst you Doug, I just feel the need to clarify incase a EV newbie reads this.

It's all about the gearing.

This is the #1 thing I agree with. The final gearing between what you measure as output power ( taken from the motor shaft on an EV, or the crank of an ICE), and the final gearing of the rear wheel.

One of the great things about electric motors is that they have maximum torque at 0 rpm, as opposed to an ICE, which literally can't even run at 0 rpm.

This is a common misconception. Motor RPM in an ICE is NOT equivalent to Wheel RPM. On the contrary, thanks to the clutch and inertia, the ICE can briefly exceed 100% motor shaft torque output. On a conventional, non-automatic ICE motorcycle, the issue comes down to rider skill. A rider can put down all of the motors output because the ENGINE RPM is NOT RELATED TO WHEEL RPM.  So if you wanted to pin the 'busa to its redline (11k) and have the wheel at zero RPM, you could apply over 100% torque by simply releasing the clutch. This of course would flip the bike over, but that is because of the huge power output of the busa. Not really fair to compare it to the zero.

A fair bike would be something like a SV650. Although it would also flip over. Because its gearing allows it several times the torque of the zero.


Meanwhile, the zero is phase amp limited. Until your motor RPMs increase, it doesnt make 100% power... (although it makes a large percentage of it)

in otherwords, your statement was backwards. A clearer and accurate statement would be:  The zeros motor cannot make maximum torque at 0 MPH, but can make a large percentage of it. The ICE can make a huge amount of torque through its gearing, but it becomes harder to apply at higher amounts.

It also makes it possible to use a fixed-gear drivetrain, which literally no ICE vehicle does.

Top fuel dragsters all the way down to Gokarts, powerboats, planes, anything where the output is not dependent on engine RPM and will allow for an idle, so tons of hydraulic couplings on most things.

That eliminates the gearbox, which is heavy, expensive, requires service, and takes up space on the bike. Eliminating the gearbox is a good thing, but it does reduce the ultimate performance of the machine somewhat.

This is very debatable, and I'll go into the performance more below...  But I have to wonder about the accuracy of the statement. A manual transmission is not heavy. They are not expensive in mass production, This application requires no clutch, They use very little oil or other lubrication, and can be made with 100,000 mile service intervals. Modern designs dont leak, and they rarely require servicing.  While a conventional motorcycle transmission would require a full bike redesign, I firmly believe that a 2 speed planatary box (1st-reduction, 2nd straight through) stuck on the end of the zero motor would be ideal. reason is below:

Think about it...how much performance could you expect out of a Hyabusa if all it had was fourth gear? Your top speed would be reduced, and the performance off the line would be uninspiring at best and require a lot of clutch slipping to do it at all. But the amazing torque of our electric powerplants make the performance off the line surprisingly good, even considering they only have a single, fairly tall gear to give decent top speed. ICEs just can't do that.

The busa goes faster than 90mph in 1st gear. so your performance off the line would remain insane, and it would continue until you hit the 11k redline.  Clearly not the bike to compare it to.
The zero motor makes similar torque to a literbike AT THE CRANK, but it literally is doing what you say above.. it is starting out in roughly 3.5 gear compared to the literbike sportbikes.

All modern literbikes can exceed 90mph in first gear with their stock gearing. They also all redline around 13,000 RPM.
The ICE motorcycles have their torque multiplied by almost twice what Zero does. Its no wonder they're so much faster.
If you regeared a zero to the same rear wheel torque level (besides having a rear cog larger than the tire) you would be just as quick, but only go 45mph. (when fully charged.)

The power is there, but how its transmitted to the ground is very far from ideal for a performance or efficiency application. The reason ICE motorcycles have multiple gears is not lack of power.. its to lower RPM for efficiency and sanity. The vibration is nuts. Its too loud.. etc.


If the zero had that two speed I mentioned above, you could leave it in 2nd, and there would be no difference than your bike now, other than a shift lever you dont touch and about 10lbs of weight. However if you put it in 1st, you could accelerate using less amps, and assuming you stayed out of the throttle, you would be more efficient around town. Plus the performance when you asked for it.   The downside would be an oil change around 70,000 miles or so... and not everyone has the throttle control (or desire) for having literbike torque at the twist of the wrist.  Also nigezeros comment about good life would go out the window, as you would shred tires if you used it alot. lol.

[Doug S]

This is a common misconception. Motor RPM in an ICE is NOT equivalent to Wheel RPM.

I didn't say it was. That's what gearing achieves, in fact it's very much the point.

Meanwhile, the zero is phase amp limited. Until your motor RPMs increase, it doesnt make 100% power.

Nope. The controller's current limit is the HIGHEST limit on an electric motor. At higher speeds, the inductance of the motor windings reduces the peak current available, which reduces the torque output of the motor. Look it up. Highest torque at 0 rpm, pretty much flat until field weakening kicks in at some rpm, ramping down smoothly to zero. Keep in mind that this is not a simple synchronous AC motor like in your refrigerator. Topologically, it's closer to a brushless DC motor, and driven by some very smart electronics.

Which brings up perhaps the biggest mistake you're making, which it seems like you've always made in your posts. You're conflating torque and power, which are very different things. Torque is the ability to accelerate a vehicle; power is the ability to dump energy into a system quickly. It's the difference between a "power lifter", whose immense strength allows him to (fairly slowly) bench press hundreds of pounds, versus a hammer thrower, who doesn't have the ultimate strength of the weightlifter, but can supply energy into a heavy weight much more quickly to throw it a much longer distance. Torque is an earth mover; power is a Formula 1 car. When and if you understand the difference between torque and power, you'll be much closer to understanding vehicle performance. A drag racer needs torque; a NASCAR car needs horsepower.

Okay, you have a minor point concerning transient conditions (fanning the clutch to rev the motor, etc.), but overall, it's about torque at low speed, power at high speed.

Top fuel dragsters all the way down to Gokarts, powerboats, planes, anything where the output is not dependent on engine RPM and will allow for an idle, so tons of hydraulic couplings on most things.

I was referring to commercially available cars and motorcycles, but okay, another minor point conceded. BUT I was also saying the engine cannot run at 0 rpm, and that's absolutely true for an ICE. You can decouple it from the wheels to keep it running, but the motor's not at 0 rpm when you do that. You also seem to have a habit of conflating rpm (engine speed) with road speed, even though you yourself made the point that they're not the same thing.

But I have to wonder about the accuracy of the statement. A manual transmission is not heavy. They are not expensive in mass production, This application requires no clutch, They use very little oil or other lubrication, and can be made with 100,000 mile service intervals. Modern designs dont leak, and they rarely require servicing.

C'mon man...however cleverly they're engineered, they're bulkier, heavier, less efficient, more expensive, and require more service than nothing. What exactly are you trying to argue here?

The busa goes faster than 90mph in 1st gear. so your performance off the line would remain insane, and it would continue until you hit the 11k redline.  Clearly not the bike to compare it to.
The zero motor makes similar torque to a literbike AT THE CRANK, but it literally is doing what you say above.. it is starting out in roughly 3.5 gear compared to the literbike sportbikes.

All modern literbikes can exceed 90mph in first gear with their stock gearing. They also all redline around 13,000 RPM.
The ICE motorcycles have their torque multiplied by almost twice what Zero does. Its no wonder they're so much faster.
If you regeared a zero to the same rear wheel torque level (besides having a rear cog larger than the tire) you would be just as quick, but only go 45mph. (when fully charged.)

The power is there, but how its transmitted to the ground is very far from ideal for a performance or efficiency application. The reason ICE motorcycles have multiple gears is not lack of power.. its to lower RPM for efficiency and sanity. The vibration is nuts. Its too loud.. etc.

*Sigh* Yes, one of the reasons ICE motorcycles have multiple gears is because you can't run them at high rpm all day. It's hard on the equipment and very inefficient. But they also need gearing because they don't make torque down low. If they did, you could simply put a single gear on the 'Busa, geared for max speed, and drive it around that way, exactly the way Zero does. If you tried that with a 'Busa, let alone an SV650, it would be an awful (if even possible) riding experience. But it works out very well on the Zero, because the Zero has enough torque down low to pull a fairly high gear right from 0 mph.

[guppie70]

@MrDude_1
You obviously know your physics! Very well stated and this fully explains why I was not blown away by the Zero SR performance.
The thing is that the Zero makes accelerating so effortless that you are probably quicker than most ICE bikes in normal circumstances. But put a Zero SR next to an R1 (or similar) with an experienced rider and the R1 will definitely beat the Zero.

[MrDude_1]

C'mon man...however cleverly they're engineered, they're bulkier, heavier, less efficient, more expensive, and require more service than nothing. What exactly are you trying to argue here?

so is the ABS system, yet people actually want them for some reason.
heavier? not noticeably.
bulkier? no. you could shift the motor over 1" (or however much space there is, and bolt it to the motor, then the trans to the frame. no additional bike bulk.
less efficient? Not extremely or even noticeably.  We're talking 1 planetary gearset with an oil bath. at a sustained full 70kw output it will never even get warm. like the weight, you're technically correct, but completely irrelevant to real world riding. that said, I bet there is a speed/rpm and acceleration range where it is more efficient.
more expensive? not really. you could use an off the shelf auto trans gearset, and the only cost would be the custom case and shaft. In a mass production of units, we're talking less than $200 per unit. On a one off basis, probably just under 1k. hardly big money, when you consider both the performance increase, and the costs of other parts.
require more service than nothing? well of course it would be more "than nothing" but it easily could go without service for 5+ years, and after that the "service" is a oil change of less than a quart.

so we're talking about a minor weight/bulk increase that is not noticeable, a cost increase that is less than the battery price drop each year, an efficiency wash, and almost no maintenance.
I dont see what you have against it with that argument.

A better argument would be that the belt drive would disappear.  The current belt is already over-stressed, and would not take the additional torque.
I would NOT ditch my belt drive for  better acceleration.

[MrDude_1]

Nope. The controller's current limit is the HIGHEST limit on an electric motor. At higher speeds, the inductance of the motor windings reduces the peak current available, which reduces the torque output of the motor. Look it up. Highest torque at 0 rpm, pretty much flat until field weakening kicks in at some rpm, ramping down smoothly to zero. Keep in mind that this is not a simple synchronous AC motor like in your refrigerator. Topologically, it's closer to a brushless DC motor, and driven by some very smart electronics.

You're confusing motor theory with the physical reality of how your bike was constructed.

further... the power vs torque argument is kind of irrelevant when you can re-gear. Since gearing is kind of the topic, I think you are the one that is losing what I am saying.... but I admit I might have said power where I ment torque or visa-versa. doesn't change the overall message.

[Electric Terry]

I am in the camp that enjoys the "sophisticated simplicity" mission Zero has used for many years.  I would rather see the cost, weight and complexity of a gearbox, go towards a controller that could output twice the phase amps.

With a gearbox you can access more battery amps quicker by getting to a higher motor RPM sooner, but with less motor rpm, and more phase amps you can still get the same power from the same battery.  So a more powerful controller would not mean any change to the battery system is needed.

When you figure a motor controller that is twice the power, it would be lighter, cheaper, and take up less space than even the smallest 2 speed gearbox.  Plus a gearbox is another component that can fail, and offers friction losses, and adds inventory and production line costs. 

The motor might benefit from having less turns per tooth with thicker coils, and that would be simple, but perhaps not even necessary.  Power will be delivered for a shorter duration to get to 60 mph than before, so it might handle the heat fine and work perfect as is, especially with the new IPM design.

Basically there is no reason in my mind to use a mechanical transmission, when power electronics can do the job so much better.

[MrDude_1]

I am in the camp that enjoys the "sophisticated simplicity" mission Zero has used for many years.  I would rather see the cost, weight and complexity of a gearbox, go towards a controller that could output twice the phase amps.

With a gearbox you can access more battery amps quicker by getting to a higher motor RPM sooner, but with less motor rpm, and more phase amps you can still get the same power from the same battery.  So a more powerful controller would not mean any change to the battery system is needed.

When you figure a motor controller that is twice the power, it would be lighter, cheaper, and take up less space than even the smallest 2 speed gearbox.  Plus a gearbox is another component that can fail, and offers friction losses, and adds inventory and production line costs. 

The motor might benefit from having less turns per tooth with thicker coils, and that would be simple, but perhaps not even necessary.  Power will be delivered for a shorter duration to get to 60 mph than before, so it might handle the heat fine and work perfect as is, especially with the new IPM design.

Basically there is no reason in my mind to use a mechanical transmission, when power electronics can do the job so much better.

While I agree that what you said will work... It reminds me of arguments decades ago about just making engines bigger instead of adding more gears.
Sure you can up the current through the motor.. then it overheats. So now you need a redesigned motor to go along with your controller.
There will be a point where it actually is simpler to have a 2speed transmission than just try to force everything through 1 gear.
Land vehicles dont have multiple gears only because of limitations created by ICE... They have them for multiple reasons.

[Richard230]

The nice thing about a gearbox is that they require lubrication and that would result in an "oil thread" on this forum.  And I really miss those.   

[Electric Terry]

Yes there are economy disadvantages from ICE engines becoming bigger and bigger.  A V8 engine will get noticeably worse fuel economy at a constant highway speed than a 6 or 4 cylinder will in the same vehicle.  Yet with an electric vehicle getting a bigger motor controller, there is no economy penalty.  The only mechanical friction (economy penalty) comes from the gearbox.   So when the power isn't needed, and just cruising in the city or at a steady speed on the highway, range would be reduced a little.  Right now we need all we can get.

I was thinking if we ever had a top speed of 150 mph I would agree that perhaps a 2 speed transmission makes sense.  But the Lightning LS-218 goes 218 mph with a single gear.  And is a rocket ship 0-60 mph as well.  I think when the conversation goes towards a gearbox, we should look what happened with Brammo, who originally was advertising the Empulse in 2010 without a gearbox, and then by 2011, one person wanted a gearbox where all the engineers didn't.  However that one person made the decisions so a gearbox was put in.  With added cost, complexity, and less space for battery, we see what happened competing against Zero.  It wasn't even close.

[Doug S]

But the Lightning LS-218 goes 218 mph with a single gear.  And is a rocket ship 0-60 mph as well.  I think when the conversation goes towards a gearbox, we should look what happened with Brammo, who originally was advertising the Empulse in 2010 without a gearbox, and then by 2011, one person wanted a gearbox where all the engineers didn't.  However that one person made the decisions so a gearbox was put in.  With added cost, complexity, and less space for battery, we see what happened competing against Zero.  It wasn't even close.

Amen. It's not just Lightning, either. Tesla does 0-60 quicker than any other commercially available car, including hypercars, with a single gear that tops out at 150 mph. The motors that provide that level of performance are roughly the size of a watermelon, weighing a couple hundred pounds. This is a luxury car produced for the mass market, not a one-off sports car. Still not enough for you? How about Killacycle? If 0-60 in 0.9 seconds isn't quick enough for you, or its top speed of well over 150 mph isn't fast enough for you, you really need to seek professional help.

[laramie LC4]

The nice thing about a gearbox is that they require lubrication and that would result in an "oil thread" on this forum.  And I really miss those.   

BEST QUOTE EVA' !!!!!

about spit my drink out at the computer screen i laughed so hard.