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ZEV is an interesting company. They've been around a long time and their focus has always seemed to be on function and durability over form. Visually their website and bikes seem to have changed little since six years ago, but they actually offer one of the most practical bikes on the market. IMO.

They're also not afraid to talk about their competitors. "Dare to Compare" has been a hallmark of their site for ages. Take with a grain of salt.

How well does the range on your LRC match their claims? They claim 80 miles at 70 mph from a 10 kWh scooter - rides lower and has a front fairing vs Zero bikes, so not an unbelievable claim. But then they claim 140 miles at 55 mph!

Zero gains approximately 22% range by dropping speed from 70 mph to 55 mph. LRC surely weighs much more than the Zero, and (per the 80 mile range claim) is a little more aerodynamic. Both of those should reduce the gain from dropping speed, but instead ZEV claims 75% more range by dropping 15 mph!

Just FYI I have today finally tested for max distance and I ended up with 187.5 km with 74 V on full throttle when starting movement. 72 V is when scooter turns off, so very close to it. I usually do not go full throttle but I did so a few times during my test to see lowest voltage / worst case voltage. Some 40-50 of these were covered with a passenger. So I'd add probably 3 km for 2 V left before cutoff and maybe 10 km taken by second rider ---> around 200 km (124 miles) on one charge if you drive like me. I do not go above 90 km/h (56 mph) and almost never accelerate with full power.

Quote from: f3flight on May 28, 2015, 04:38:18 PM

Just FYI I have today finally tested for max distance and I ended up with 187.5 km with 74 V on full throttle when starting movement. 72 V is when scooter turns off, so very close to it. I usually do not go full throttle but I did so a few times during my test to see lowest voltage / worst case voltage. Some 40-50 of these were covered with a passenger. So I'd add probably 3 km for 2 V left before cutoff and maybe 10 km taken by second rider ---> around 200 km (124 miles) on one charge if you drive like me. I do not go above 90 km/h (56 mph) and almost never accelerate with full power.

2V left ? What is the battery type ?

I believe f3flight meant the final battery voltage in his test was 2V above the lower cutoff voltage.

PROTOMECH,
Thanks for the input.  You are onto one range factor when you mention fairings.  In regard to your comparison to the ZERO range and comment on a fairing, we just finished a years testing with meters on several bikes measuring power consumption.  To our surprise, we found that the ZEV T8500 and a new prototype motorcycle in testing, both naked motorcycle style like the ZERO, returned a consistent 17% higher watt hour consumption per mile in the 55 and 70 mph tests compared to the faired scooter bodies of the S Series and LRC.  This is one of the reasons that ZERO recently stated they intend to work on a fairing for the ZERO.  We found that the LRC does better than the S Series slightly which we believe is due to the length of the LRC and a sort of “tail” that aids streamlining.  Flat out on a flat road, when ran with the same motors, controllers, etc. , the LRC ekes out a bit of speed advantage on two bikes running side by side weighted to the same weight.

You are correct that the ZERO rider sets much higher and makes a bigger air dam for even more drag vs the ZEV T8500.  Not sure how much exactly, but I would figure another 2-3% giving about a 20% advantage to the ZEV in aero.

In addition to the fairings, there are a few other big differences in the designs that eat into range. 
--First is the belt drive on the ZERO.  Belts and chains do not transmit power without losses.  Estimates of power losses run as high as 12% at max load.  In constant speed power transmission 4% is considered the minimum losses.  The ZERO runs a very high reduction ratio.  Look at it from the side and you can see that the ratio between the front and rear sprocket is much higher that the ratio typically seen on a gas bike.  High ratios incur additional losses, but it would be pure speculation to guess what the effect might be.  The 4% is not just during power on, it is a loss in glide distance also.  Since ZEV runs a hub motor, we do not suffer those losses thus gaining in range. 
--Second- motor internal design.    ZEV runs 1200 rpm down the road at 80 mph, a ZERO is about 4300 rpm.  When you turn a motor at high rpm, you suffer internal windage losses.  The rotor in the ZERO is zinging in an enclosed space and creates pumping losses.  The ZEV uses big vent windows internally through the stator to minimize that effect.  This can be worth 4-5% depending on the motor.  Opening the  motor up with vents yielded 3.7% on a drag race motor we ran that was a non hub motor.  Works on piston engines the same.  My race car jumped 17 hp from porting vent holes between the cylinders in the main bearing support webs.  Newer car engines now generally do this.
--Torque lag occurs when the throttle response is not instantaneous and you are basically pouring the amps to the motor and waiting for it to rev up.  That “excess” amps used to reach a given speed where the amp draw will decline at constant load is a range killer.   Motor torque on a ZERO S is listed at 92 Nm.  Its 161 Nm on a T8500 or 220 Nmon the top ZEV motor.  But it’s not just that we have more than double the torque, it’s that we make that torque on only 150 amps.  So when you roll on the throttle on the ZERO, it takes time to gain rpm, and your using higher amps than to accelerate at the same rate.  Time X amps is lost watt hours and lost range.
--Efficiency curves are not the same for all electric motors.  How you wind them puts the torque and or the efficiency at a given rpm A ZERO S is listed as having a top speed of 95 mph, and a sustained speed of 80 mph.  We just set the torque by the motor windings to put the efficiency in the 55-70 mph band.  No reason to lose range to gain the ability to make a short run to 95 mph.  80/95 would indicate the torque band for testing for range at 70 mph is off by 15.7%. as a rough figure, and it would be more as the aero drag goes up exponentially with speed.  Rather like running your car in 4th instead of overdrive. 
--Motors are not the same flat efficiency throughout the rpm band.  While someone may state their motor is 87-90% efficient, that is at only one spot on the rpm and load band.  At top speed, motors are generally under 10% efficient.  So being 15.7% off on the matching of the motor efficiency point to the range measurement points of 55 and 70 mph will cost you dearly.  Moving the rpm band on a motor by 15% could cost you as much as 45% efficiency.  This is where I think the ZERO loses much of its at 55 mph range.  You just cannot make a highly efficient 55 mph machine that runs 95.
--Heat is the next factor.  As shown in some video on YouTube of the ZERO SR, two acceleration runs to 60 mph from a dead stop made the system register overheat and pull back the power when made in the max power mode.  Torque lag causes motor temperatures to soar.  So does running out of the efficiency band as for some 55 mph test.  Heat in a motor costs you power and efficiency.  Loses just soar.  The hub motor is spinning making its own fan.  It has more surface area to get rid of the heat.  It uses the wheel rim as a “cooling fin”.

Now take all of the factors above into account and you can see why the ZEV wins the range wars.  The 10 kw ZEV out distances the 12.5 kw ZERO consistently.

Now let’s take F3s results. 
First, he states he got 187 km range from the bike.  115 miles.  And he calculates that he could reach 124 miles.  So there is your proof period that his 115 miles or his 124 miles beats the  94 miles of the ZERO, or any of the other mileages that they list at any speed or combination of speed despite the fact that the ZERO has a 25% larger battery.  All of those efficiency factors just kill them.

So how did he get less than 140 miles?  First and foremost, he was not running in controlled circumstances as we or ZERO did.  He had varying speeds, roads, etc.
A major factor is he has snow tires on his bike according to his emails from me because he drives year round through Moscow Russia winters.  An article published on Tire Review discusses the cost saving benefits of fuel efficient tires. “Studies show that 20% to 30% of a vehicle’s fuel consumption and 24% of road vehicle CO2 emissions are tire-related.”  Mileage is significantly decreased with snow tires.”   So just putting on snow tires kills the range.  Anyone want to dispute that?  Know of any ZERO with snow tires on them?

I love the mileage F3 Dimitry got.  I think we will post it on the web site.  It just proves we kill everyone else in range (even with the snow tires).  So when you say "take the (ZEV) Dare to Compare with a grain of salt", remember this case. 31% better range than the ZERO on 25% less battery –while driving on snow tires (by Dimitry’s tests).   ZEV never makes a claim we cannot prove.  Too much low hanging fruit like this to point to without trying to create any truths or requiring a grain of salt. 

Dimitry

As to using snow tires, I can only go by your emails to me that you were buying Michelin snow tires.  I cannot know what you did, only what you told me you were going to do.

As to range of a ZEV vs a Zero , you do not understand what you are writing about.  If you are going to quote ranges and specs, make it an apples and apples test vs test.  We do not publish the City test you quote on the Zero for the ZEV because the tests are so misleading to would be customers to the point of being a joke.

Go to the Zero page  http://www.zeromotorcycles.com/zero-s/specs.php    The ZEV 140 mile / 225 range is at a steady 55 mph, flat land as per the same tests ZERO uses for their 55 mile range.  Using the exact same test, the ZERO advertises 115 miles / 185 km.  So by the ZERO web site, they advertise that under the same test, they get 40 less km range than a ZEV.  You understand that?  Less range claimed by Zero in the same government tests.

So  you can see that in the 55 mph test, ZEV beats the ZERO, even with its power tank, by 25 miles / 40 km.   A 15.3 kw Power Pack gets beaten by a 10 kw ZEV.
Now you say that you believe that the 298 km range of the Zero in City test should be real world, and not a 55 mph flat land test.  You could not be more wrong as follows.

You quoted the  298 km range of the ZERO in the “city” driving test.  Click on the ? behind the word city and you will get  “A “City” range test is specified to determine riding range during “stop-and-go” operation typically found in urban areas. This estimate is provided following the SAE J2982 Riding Range Test Procedure for On-Highway Electric Motorcycles to provide a reasonable and consistent basis for manufacturers to inform prospective owners of the riding range that can be expected under specified operating conditions. Actual range will vary based upon riding conditions and habits.”

So now you need to look up the SAE J2982 test.  Go to http://www.mic.org/downloads/MIC-recommended-practice-riding-range-test-procedure-for-on-hwy-electric-motorcycles-042412.pdf   But then you see that you have to go to http://www.epa.gov/oms/standards/light-duty/udds.htm 

What you learn is that
•   This test is not driven on a road at all by an actual rider.
•   This is not a road test.   
•   It is run on a dyno with no rider weight, no aerodynamic factors, etc.  The throttle is not even used by a person, it is slaved to a computer.
•   The speed used is 19.59 mph / 31.5 kmh
•   The test sequence is for 7.45 miles / 12 km (and repeated until the bike shuts off)
•   No braking is ever done

This is why there is the giant jump in the ZERO specs from the 55 mph test results to the City test results of a factor 1.6
But you are really focused on the City number that we do not advertise because of its misleading nature.    You want apples and apples.  So the ZEV results for the City test is 245 miles, 395 km.  So in City test vs City test, we beat the Zero by 97 km.  97 km Dimitry.  The higher torque at lower rpm of the ZEV gives us an advantage in this type of test. 
Since all of these tests are done at EPA facilities and or under controlled circumstances, there is no funny business by either company. 
As to a complaint that the storage lids coming open as being your fit and finish issue, I would assume that part of that is cold weather shrinking the plastic.  But regardless, in your rear rack package that was not picked up are a set of parts to lock the lids to fix your issue.
Since you are willing to spend another $6,000 to get less range, perhaps you would like to use some of that fix your wish list.  If you want more range than you already have, perhaps you should consider a Range Pack for the ZEV that can fit in the under seat compartment. 
Your rear rack was returned from Latvia and is laying here waiting for you to tell us where you want it sent as per previous email to you.  I am waiting for your instructions.