View Full Version : ME1003 Specs

15 October 2015, 1230
Hi Guys,

Really confused with motor spec of the ME1003 being advertised differently from different suppliers in relation to RPM.

If I am correct Max Voltage is max RPM nevermind amperage (lets say unloaded)

On the EV drives they say (3050 rpm at 72V Unloaded) but on the data sheet to download it says max rpm 5000 so i cant really trust it.
Thunderstruck says 3700 rpm unloaded and 2800rpm loaded
confusing and I cant trust it for my calculations...

I guess 3050rpm is max continuous and 5000 is max peak for one minute @ 400Amps??

Has anybody with this motor an idea of actual max loaded rpm and at what voltage??

16 October 2015, 0253
...all depends on the load dude.

Unloaded is one thing, but it's not at all indicative - what you're more likely to find out looking for max speed unloaded, is what speed the whole thing turns into a grenade at - which is of course, nothing to do with the speed it will do when it's loaded.

You're right in that the voltage you apply dictates your maximum RPM, but you have to be able to apply that voltage.
Any load will lead to increased current consumption and then sooner or later you reach your limit based on either approaching the thermal limits of the motor, or voltage sag in the battery pack.

So - long story short, without a fully quantified apparatus, it's an entirely subjective number.

Best guess you'll be able to make for the sake of your calculations is to quantify the load, then look at the max current your pack can deliver and the voltage it can deliver it at; the voltage will tell you the rpm you can run, and the current will tell you the max load you can run at that rpm.

16 October 2015, 0538
I believe 5000 rpm is the mechanical limit. Where the motor will tear itself apart from centrifugal force.

Sent from my SAMSUNG-SM-G850A using Tapatalk

20 October 2015, 1046
Thanks Guys, i was on the right track so... was just confused about the 5000rpm stated but that makes sense now.

20 October 2015, 1618
Here is a product info sheet with ME1003 specs: http://www.evdrives.com/v/images/Motors/ME1003/Product_Info_ME1003-1.pdf

This is the only place I have found that states it is rated for 96V.

21 October 2015, 0405
Yeah saw that, might be interesting as it gives you a chance to upgrade to higher voltage, I can only do 72v with leadacid due to space.

Has anybody an idea or even a graph showing the torque and amp when under full acceleration?
I am trying to calculate the acceleration that i will be getting from my "imaginary"bike.

Specs I have in my calculator (Lennon Rodgers calculator heavily modified)...
72V/80Ah Leadacid
Total mass 390kg (including rider)
time to 80kmh = 9.5s (to achive that I need 82Nm from the go off the line up to 93Nm at finish off acceleration at 80kmh)
gear ratio 3.5
Wheelradius 0.32m
frontal area 0.7m2 and air drag coeff of 0.6

With this setup i could theoretically do 97kmh at 2800rpm

Would be nice to know if someone could confirm that the acceleration is realistic?
Unfortunate that most people I found on youtube dont put their acceleration data in their specs. Any data is very welcome :-)

Electro Flyers
21 October 2015, 0815
Try talking to this guy on the Adventure Rider forum: http://advrider.com/index.php?threads/so-i-built-an-electric-motorcycle-that-does-90-mph-with-a-70-mile-range.1099258/

He started out with a ME1003. Apparently it burned out after 11,000km, and he switched to a AC20.

21 October 2015, 0920
Went through your calcs and they check out. My own follow.

Based on the numbers you've provided, and assuming an armature diameter of 6" (housing is 8" so that seems logical enough), then the force required at the edge of the rotor, in order to produce the 93Nm you've calculated a being required, is 1240N. (Nm/rotor radius[0.075m]).

You require this force at your terminal velocity of 80km/h (23m/s) which happens at a wheel rpm of 670 [edited from 2400 in response to correction pointed out in post #10 below].

With your gearing and combined wheel-tyre radius, that requires a rotor angular velocity of 252.8rad/s.

Given a rotor radius of 0.075m as per the assumption above, that translates to a linear velocity of 19m/s at the rotor edge.

Your power requirement at the rotor edge then is N.V -> 1240*19=23560W

The V/RPM constant for the ME1003, according to the datasheet, is 0.02; this means that 2400rpm happens at 48V.
Your current requirement for this performance is subsequently in the region of 490A.

According to the datasheet, peak stall current for the motor is 500A, and it can take that current for 10 seconds.

So - to answer your question - that acceleration is achievable, but you're pushing the ragged edge of what the motor can do.

On the other hand however, a 72V pack can get you 3600rpm, so if you could up your gear to from 3.5 to 5, you could get the same performance from about 230A.

Podolofsky, feel free to take a look through those numbers just in case I've made any errors in there, but I'm reasonably sure it's all correct.

21 October 2015, 1823
I have the ME1003 with 72V and 450A in my elmoto spreadsheet (also a modified Lennon Rodgers). With 390kg and 3.25 gear ratio I get 0-80 kph in around 8-9 sec.

Electro Flyers
21 October 2015, 2001
You require this force at your terminal velocity of 80km/h (23m/s) which happens at a wheel rpm of 2400.

Do you mean the motor armature(rotor) RPM? Because I calc the wheel RPM at ~670, with a .32m radius wheel(.64m diameter, 2.01m circumference) at 80km/h.

22 October 2015, 0232
Just checked that - you're right, that 2400 is the rotor/armature rpm - apologies.
The rest of the numbers are correct though so it would appear that that mistake was solely in the description of the value. Crosscheck reveals that I appear to have used it correctly.
Sorry for the confusion - knew I'm muck something up. :p