Suggest 52v/30Ah battery for Voodoo Hoodoo e-bike

Nothing in the link states the max amp draw of the controller. Without that info it's impossible to know how much amperage the battery you get needs to be able to put out. Many cheap 18650 packs are limited to under 30A. Some small packs are rated for 20A or less. It would be wise to have the battery pack be capable of twice the amp draw of the controller.
 
wesnewell said:
Nothing in the link states the max amp draw of the controller. Without that info it's impossible to know how much amperage the battery you get needs to be able to put out. Many cheap 18650 packs are limited to under 30A. Some small packs are rated for 20A or less. It would be wise to have the battery pack be capable of twice the amp draw of the controller.
Thanks for the reply.

I'll ask the seller for more info on the max amp draw of the controller. Any other info I should ask for that are relevant to selecting an appropriate battery?
 
wesnewell said:
Nothing in the link states the max amp draw of the controller. Without that info it's impossible to know how much amperage the battery you get needs to be able to put out. Many cheap 18650 packs are limited to under 30A. Some small packs are rated for 20A or less. It would be wise to have the battery pack be capable of twice the amp draw of the controller.

My e-mail to them.

Could you provide me with info about the controller used in this bike?
What is the max amp draw of the controller?


Their reply.

The Controller switches to cope with 38V 48V or 52V.

A 60V option will have a controller that operates at 60V using Sinewave.


Is this helpful at all? Shouldn't they be able to specify the exact make/model of the controller?
 
It's certainly not helpful in selection of a battery pack except for the voltage. If they can't answer a simple question like this, don't expect any help from them if you run into a problem. 50 mph, as stated in the link, takes at least 5000W of power. At 60V, that means the controller has to draw ~85A from the battery. The 1500W motor will burn up in a few minutes at that rate. I'd be weary of any claims they make.
 
Aliexpress is a plattform not a dealer. Could you recommend buying at ebay?

You have to include shipping cost, taxes and the risk that you will get no battery at all.

You also have to include the risk of getting a "Lithium bomb" buying cheap battery packs from China or elsewhere.

You can make things cheap, but you can't make them cheap AND also good quality. At least not batteries...

In the end it is your decission. Good luck.
 
wesnewell said:
It's certainly not helpful in selection of a battery pack except for the voltage. If they can't answer a simple question like this, don't expect any help from them if you run into a problem. 50 mph, as stated in the link, takes at least 5000W of power. At 60V, that means the controller has to draw ~85A from the battery. The 1500W motor will burn up in a few minutes at that rate. I'd be weary of any claims they make.
I am amazed to hear that! This bike was featured on this British morning show and the resident "gadget guy" specifically mentioned a top speed of 50mph and an assisted range of 150kilometres. https://www.youtube.com/watch?v=mPdXahSoUo4
 
Cephalotus said:
Aliexpress is a plattform not a dealer. Could you recommend buying at ebay?

You have to include shipping cost, taxes and the risk that you will get no battery at all.

You also have to include the risk of getting a "Lithium bomb" buying cheap battery packs from China or elsewhere.

You can make things cheap, but you can't make them cheap AND also good quality. At least not batteries...

In the end it is your decission. Good luck.
The ebike seller is selling a 52v/20Ah battery with top quality Panasonic cells (and the charger) for £500. Is that a reasonable price for a battery of this size? He said the cells are made in Japan and the battery is assembled in China, then imported to the UK.
 
You might want to watch the video again. He states 50 to up to 75 KPH, not 50 mph. That's more realistic for a 1500W motor, but that up to 75 kph is going to be with a small rider and no wind. That's 46.5 mph, and I highly doubt it will do that under normal conditions. And the 150 K range is not at that speed either. Lots of hype for the viewing audience. I run 88.8V battery (24s lipo) on both a 1000W and 3000W motor. both will do over 40 mph on level ground. But the 1000W motor would melt after not too long at top speed. The 3000W motor will do 40 mph all day long, until the battery is dead.
 
Yeah stay away from that seller on Aliexpress.

Buy the 1500W Leaf motor or 3000W MXUS motor, a sinewave controller from any number of reputable sellers, and any bike you wish. Be sure its steel and use Torque Arms.

Battery could be from E.S. Tumich, Luna, ebikes.ca, Home Depot EGO 56V packs, Hallomotor/Conhismotor on ebay sells batteries, Sears.com, cant think of any others without searching.

http://bikesdirect.com/

https://endless-sphere.com/forums/viewtopic.php?f=3&t=87126#p1273132
 
wesnewell said:
You might want to watch the video again. He states 50 to up to 75 KPH, not 50 mph.
1. Watch the video again. He mentions that the motor is 1.5KW and then says "It's capable of pushing this bike, unassisted, at up to 75kph". He never says "50 to up to 75kph".
2. I said 50mph in my original post because that's what the seller is claiming on his website. In any case, 75kph is about 47mph, rounded to 50mph.

wesnewell said:
And the 150 K range is not at that speed either.
The 150 kilometre range that the presenter is talking about is for regular cycling speeds which I assume is 10-15mph, at least for most people.

wesnewell said:
I run 88.8V battery (24s lipo) on both a 1000W and 3000W motor. both will do over 40 mph on level ground. But the 1000W motor would melt after not too long at top speed. The 3000W motor will do 40 mph all day long, until the battery is dead.
Does this mean that the 1500w motor can do 25mph all day long too?
 
markz said:
Yeah stay away from that seller on Aliexpress.

Buy the 1500W Leaf motor or 3000W MXUS motor, a sinewave controller from any number of reputable sellers, and any bike you wish. Be sure its steel and use Torque Arms.

Battery could be from E.S. Tumich, Luna, ebikes.ca, Home Depot EGO 56V packs, Hallomotor/Conhismotor on ebay sells batteries, Sears.com, cant think of any others without searching.

http://bikesdirect.com/

https://endless-sphere.com/forums/viewtopic.php?f=3&t=87126#p1273132
Do you mean that I should stay away from Aliexpress in general or a particular seller on Aliexpress?
 
A 1500W motor should be able to do ~35 mph continuous without a problem.
 
wesnewell said:
Nothing in the link states the max amp draw of the controller. Without that info it's impossible to know how much amperage the battery you get needs to be able to put out. Many cheap 18650 packs are limited to under 30A. Some small packs are rated for 20A or less. It would be wise to have the battery pack be capable of twice the amp draw of the controller.
The seller pointed me to the page with the controller's technical info (http://www.ebay.co.uk/itm/1500W-Electric-Bike-Kit-inc-52V-21ah-Battery-121-Build-Assist-/222440803370?var=&hash=item33ca814c2a:m:m3IsptddIjE-GoRo30FEIeQ)

The Max. Current: 45±1A
 
If you go to http://www.ebikes.ca/tools/simulator.html, you can use the simulator to try different voltage/motor/controller combinations, even changing the grade or slope to see the effects of hills. These data are based on lab tests performed by Justin at Grin Technologies.

In your circumstances, a 52 volt battery with 45A controller pushing a standard 4T wind hubmotor will give an average weight rider about 53 kph on level ground. If you lift the wheel off the ground, it would spin at about 75kph, so the seller is correct in saying that "It's capable of pushing this bike, unassisted, at up to 75kph" given a steep enough decline of course.

It is the motor winding and voltage that determine top speed (given enough current in amps to push it there). A "500W" and a "2000W" direct drive motor of equal winding will have similar top speeds at a given voltage; the difference between the two motors is copper mass, and the smaller motor would burn out quickly at 2000W.
 
molybdenum said:
If you go to http://www.ebikes.ca/tools/simulator.html, you can use the simulator to try different voltage/motor/controller combinations, even changing the grade or slope to see the effects of hills. These data are based on lab tests performed by Justin at Grin Technologies.

In your circumstances, a 52 volt battery with 45A controller pushing a standard 4T wind hubmotor will give an average weight rider about 53 kph on level ground. If you lift the wheel off the ground, it would spin at about 75kph, so the seller is correct in saying that "It's capable of pushing this bike, unassisted, at up to 75kph" given a steep enough decline of course.

It is the motor winding and voltage that determine top speed (given enough current in amps to push it there). A "500W" and a "2000W" direct drive motor of equal winding will have similar top speeds at a given voltage; the difference between the two motors is copper mass, and the smaller motor would burn out quickly at 2000W.
How do I select the appropriate values for the first three parameters in the simulator? The ebay listing of the kit I am interested does not provide this information. Or are you able to deduce them from the specs?

Is standard 4T wind hubmotor = CLyte 4xx?
There is no 52v/21Ah battery in the drop-down box. You can specify a custom battery setup but you need a third value (ohms something)

molybdenum said:
the smaller motor would burn out quickly at 2000W.
Does this mean that if both motors are run at a high speed, say 30mph, the 2000w motor will be able to maintain that speed for far longer than the 500w motor?
 
minime said:
How do I select the appropriate values for the first three parameters in the simulator? The ebay listing of the kit I am interested does not provide this information. Or are you able to deduce them from the specs?

You'll have to contact the vendor asking for turn count, or better yet, the KV value (RPM per volt) for the motor, then many on this forum could advise a reasonable substitute motor for the simulator. I'm guessing that most 1000W ebay motors will resemble the clyte HS3540 in KV, which is 10.4 RPM per volt. Higher turn count motors have lower KV and spin slower at a given voltage and vice versa.

minime said:
There is no 52v/21Ah battery in the drop-down box. You can specify a custom battery setup but you need a third value (ohms something)

If you get a poor quality battery, it will have a high internal resistance, which results in heat generation and severe voltage sag (voltage drops sharlpy when battery is under load, reducing speed). You can play around with the resistance values to see the effect of changing it. In general a higher Ah battery will sag less than the equivalent lower Ah battery at a given load, as there is less current demand placed on each cell in the pack.


minime said:
Does this mean that if both motors are run at a high speed, say 30mph, the 2000w motor will be able to maintain that speed for far longer than the 500w motor?

I would expect a 2000W rated motor would run all day without overheating at 2000W power (depending on vendor honesty), but it is heavier and more costly; some members prefer to overclock a lighter motor (1000W) and monitor its temperature. Basically, the wattage rating of a motor is meaningless in terms of speed or performance, and refers to the copper mass and its ability to shed heat at a given power input. You can run any motor at whatever voltage and amperage you choose within reason. The simulator will predict how long a motor will run before overheating using different battery/controller combinations, and these estimates are a bit conservative.
 
markz said:
Will you be buying that bike?
I do want to buy that bike but I am concerned that I might be overpaying, especially since I've found other "1500w bikes" at half the price (~800 instead of ~1600).

Actually, I attempted to buy the bike via Ebay but the purchase was cancelled by the seller. He did ask me first and I accepted. Does that reflect badly on the seller? I think that Ebay charges him 10% of the final price so it makes sense (for him at least).
 
molybdenum said:
You'll have to contact the vendor asking for turn count, or better yet, the KV value (RPM per volt) for the motor, then many on this forum could advise a reasonable substitute motor for the simulator. I'm guessing that most 1000W ebay motors will resemble the clyte HS3540 in KV, which is 10.4 RPM per volt. Higher turn count motors have lower KV and spin slower at a given voltage and vice versa.

According to the Ebay listing at http://www.ebay.co.uk/itm/1500W-Ele...attery-121-Build-Assist/222440803370#rpdCntId, Max. Speed: 600RPM. Is that it? Maybe it's 600RPM / 48V = 12.5KV?
 
minime said:
According to the Ebay listing at http://www.ebay.co.uk/itm/1500W-Ele...attery-121-Build-Assist/222440803370#rpdCntId, Max. Speed: 600RPM. Is that it? Maybe it's 600RPM / 48V = 12.5KV?

The ebay listing does indeed say 600RPM and 35Nm of torque :shock: . This would be an insanely fast wind motor which would accelerate sluggishly and have an unloaded speed of 80 kph in a 28" wheel under a normal 48V 30A (1500W) regime. I don't know of any ebike motors with those parameters? Also, I'm not sure if the controller would be pre-programmed for 30A, which would deliver the promised 1500W. Pushing 45A at 48V would be 2250W. To further confuse matters, note that a 10KV motor run at 48V, 20A behaves nearly identically to a 5KV motor run at 96V 10A, with the 10KV motor having a modest advantage in efficiency. So you could run a very fast wind motor by increasing amps and reducing volts (or not :twisted:) - some here swear by it. Under the listed specifications, I'd be concerned about burning out the motor on even modest hills.

In short, I don't think the vendor knows what they're selling (I at least hope not).
 
molybdenum said:
Under the listed specifications, I'd be concerned about burning out the motor on even modest hills.

In short, I don't think the vendor knows what they're selling (I at least hope not).
Damn, I am disappointed to read that. I was fired up and ready to buy that bike after watching this review on TV (https://www.youtube.com/watch?v=mPdXahSoUo4)

Was the presenter bribed?!? Or maybe that's not even the bike I would have paid for (even though the seller claims it is).
 
I'd be surprised if the listed specs were listed correctly, as the numbers don't make sense to me. A typical ebay fast wind would be about 380RPM, and even these would struggle in a larger wheel. That being said, the fastest winds (2T) are ideal for small wheel builds and high amp setups.
 
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