If i put a hub wheel on the front and the back i will go faster right?
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No, you'll still retain the same top speed as only having one kit and you'll only gain a bit of extra torque and acceleration but the extra weight added would probably negate that by a lot so it's not really worth it.Last edited by HIGHVOLTAGE; 07062018, 12:03 AM.

Better to just use one high power motor.


do you favor samsung 30q or the 25r for single track riding 750bfang I am trying to figure out if I would be better off with two mini cubes and run them parel with 30Q cell verse the single battery that is already 12.5A with 25R cell any help would be greatly appreciated??
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I bought a "48v Advanced 300w Luna Charger" less than 6 months ago. For some reason it will not charge my battery anymore, Please help!! Always a green light no red.
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More details needed. There can be like 20 different reasons a charger is failing to charge a battery and half of those reasons may not even be related to the charger itself
Check this thread for details and tips.
https://electricbike.com/forum/forum...ctricalissues


Is this Kelly controller compatible with the Luna Cycle 7,500 Watt BLDC motor and hall encoders?
http://www.evassemble.com/index.php?...fegecjt7c3mjl5
http://www.servovision.com/KellyKBLUserManual[1].pdf
I'm a little disappointed in the stock controller (for my application only, it's probably great for you application) and I'd like to try a programmable controller.
This Kelly looks like it meets the requirements for the motor, but I'm not 100% sure.
72 Volt input: CHECK, 100 Amps: Check.
I don't know how many poles the motor has, and if it has more than ten poles I won't be able to hit 4,000 RPM on the motor. If it has more than 20 poles, I won't be able to hit my target sped of 30 MPH.
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By adding 4 series and 4 parallel batteryies will a motor be overloaded or does a controler have a resister or something in it? Also will this increase my distance taking away the extra 44 pounds of lead acid?
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You mean keeping the 4 in series but adding a parallel string of another 4 in series? That would be fine. But you are doubling the weight. 88 pounds of batteries versus just using a jumbo shark or killer whale at ten pounds.
Adding extra capacity does not affect the controller, the controller only takes what it needs. Adding extra voltage may affect the controller though.


Hello all. Just installed BBSHD Kit with 52V 28Ah Battery from Luna Cycle. I have the the 300 Watt Advanced Charger. When I plugged in the charger for the first time, it showed 58.8V, green LED is on, no fan activity. I doubt the battery was shipped fully charged. The little voltmeter shipped with the battery shows something like 48V with the charger unplugged and 58.8V with the charger plugged in. The DPC18 shows 60% battery.
I think the battery isn't charging. Any thoughts?
P.S. I've tried various sequences of powering the charger and connecting to the battery, waiting 30 seconds each time. Also various Amp and % rates on charger. Same result.
P.P.S. I've left the charger connected to the battery for several hours; no change. When I unplug the charger, voltage drifts down on charger display and voltmeter.Last edited by jjs; 07062018, 03:57 PM.
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I used the lightbulb testing method. With a 53watt bulb, it looks like it is pulling 0.27 Amps.
It is:Not using any adapter. I don't have a multimeter, but I'm thinking that because the little plugin voltmeter shows 58.8 when the charger is plugged in suggests that the charger is working.TRIANGLE 52v Panasonic GA 18650 24ah Pack HIGH POWER + LONG RANGE 52TRI24GA Last edited by jjs; 07092018, 09:34 AM.
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I would agree but it would still be best to test with a multimeter if at all possible. Anyway looks like this might be DOA, please email support@lunacycle.com your order# and we'll handle it.


Please DO NOT SHIP order ID #56868!!!
I've called and emailed . Do not ship it!
This was for a 60v Triangle 24ah Panasonic GA
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Quick question. I'm looking for a 40amp cont. 52vcompatible Controller for my ebike. It's currently a 1500w controller, looking to upgrade to about 2000w. My battery could handle a max cont output of about 40 amps. Do you guys sell anything that would fit the bill?
Thanks
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Hello guys,
What tool or method was used to remove the bafang ultra G510 rotor in this luna video ?
Unlinke BBSxx there is no shaft to vicegrip onto and I risk damaging the bearing if I clamp on it.
Thanks !Luna cycle tears down a Ultra mid drive and compares to the popular bbshd. https://lunacycle.com/bafangultramotorebikemiddrive/ check out the Apex Bike ...
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Originally posted by Weht View PostHas anyone come across come across the problem of a hub motor over heating. On my way home and a little bit after that my wheel was hardly going at all. It was like i was just pretending to rev a motorcycle, but after a half hour it seemed to work better.
The explanation for what you experienced is the effect of the equation P = (i^2)R. P is power in watts, i is current in Amps and R is the resistance of the copper of your circuitry in Ohms.
As your motor increases in temperature, the resistance (R in the equation) in the copper of the wires increases https://www.cirris.com/learningcent...ientofcopper. Anytime you operate the motor, you draw current and the motor produces power in the forms of both heat as well as useful, locomotive horespower, so that the motor temperature is all the while increasing. Once the copper gets to a certain point (above 100 degrees C), your hub motor is a more efficient heater than it is an efficient device for producing torque. Once you are at ridiculously high temperatures for a hub motor (say, 120 degrees C), the motor is effectively a heater.
The best solution is to obtain a larger mass of copper in your wiring. You can accomplish this with larger gauge wires and/or heavier (some people would say wider) motor windings. If you can manage to increase the mass of copper in your wiring, the physics will work for you rather than against you.
A more economical way to fix this problem is to reduce the current. You see from the above equation that the power (think heat) is proportional to the square of the current used. If you double the current, you quadruple the heat. If you use four times as much current, you get 16 times as much heat! On the flip side, if you reduce your current by 25%, you reduce your heat by 43.75%.
Here is the example of reducing current by 25%:
If you are now using 40A and the resistance of your motor is R Ohms, the heat is P = (40 X 40) X R = 1600R Watts.
If you reduce your current by 25% and only use 30A, the heat is P = (30 X 30) X R = 900W.
Going from 1600W down to 900W is a reduction of 700W, so you have reduced your heat by {[700/1600] X 100} = 43.75%.
Note that reducing the current by 25% reduces the heat by 43.75%.
Note that (75 X .75) = .5625, and 1.000  .5625 = .4375. This is saying "use 75% of the initial current, and generate only .75 X .75 = 56.25% of the initial power (heat)".
Following this, we see that using 50% of the initial current will generate (.50 X .50) = 25% of the initial heat.
Similarly, reduce current by only 10% and generate only (.90 X .90) = 81% of the initial heat. At 100 degrees C, you would have to drastically reduce your current; at 81 degrees C, you would just keep on riding!
If you read all of that, here is your bonus: it is also the case that P = (v^2)R with P in Watts, v in Volts and R in Ohms. So all of the above applies to Volts as well as Amps. Reduce voltage by 25% and reduce heat by 43.75%, etc.
This is why I always advise people to use a large motor in the first place. A large motor is heavier and a little more expensive (that's the copper that you want!), but in doing this you are in the best position to draw plenty of current and not worry about overheating. The worst that can happen here is you have a slightly heavier and more expensive ebike, but the motor will run cooler in all applications, operate at optimum temperatures for longer periods of time (longer rides!) and last years longer than a motor that operated much of its life at the upper limit of its capability.
In the link above, it says that "if the temperature (of copper) increases 1°C, the resistance will increase 0.393%". Looking at either P=(i^2)R or P=(v^2)R, we see that the relationship between heat (P) and resistance (R) is linear, so the increase in the temperature of the copper does not dramatically increase the heat, but a continued input of high current (or voltage, but our systems have their predetermined ranges of voltage), at any temperature, does dramatically increase the motor temperature.
In my day to day ebike riding, I will stop riding at a motor temp of 100 degrees C. If I see 90 degrees C, I back way off the throttle, riding at a much lower speed, and keep an eye on the motor temp. The motor temp decreases while riding along at the much lower speed.Last edited by commuter ebikes; 07072018, 04:43 PM.
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