What make is this Hubmotor and is 350w

Nealh

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Looking at the markings it is a 350w hub, as too producer ? Most certainly one would think China.
To me the design looks like it is might be one with an integrated controller !!!
 
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Andy1865

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Thanks Neal. So coupled with a 16ah battery and 48v what would it be watt wise?
 

mike killay

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Nealh

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Your link and the pic of the hub with the markings don't add up, the hub pic in #1 though not 100% clear does look like it reads 350w nom and not the 750 nom in the Russian link.
 

Andy1865

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Cheers Mike ya a star for finding that info. The bike has a 16ah battery, 48v controller and i was told it was a 350w motor....but im poss wrong its high which is good.
 

Andy1865

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Your link and the pic of the hub with the markings don't add up, the hub pic in #1 though not 100% clear does look like it reads 350w nom and not the 750 nom in the Russian link.
Very confused.com
 

Nealh

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It's possible the LF-05X comes in different Wattages or with varying wattage markings.
A bit like Bafang BPM/CST hubs 250, 350& 500. The marking just suits the market it is marketed at. For Instance yanks will steer clear of 250w marked hubs but are quite happy with 350/500 marked ones, though likely they may be all the same inside.

End of the day the motor wattage is what ever the producer places on it rather then what it is tested as ?
 

Andy1865

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It's possible the LF-05X comes in different Wattages or with varying wattage markings.
A bit like Bafang BPM/CST hubs 250, 350& 500. The marking just suits the market it is marketed at. For Instance yanks will steer clear of 250w marked hubs but are quite happy with 350/500 marked ones, though likely they may be all the same inside.

End of the day the motor wattage is what ever the producer places on it rather then what it is tested as ?
Thanks Neal, so if the motor is 350w lets say and the battery is an LG 16ah and the controller is 48v what should poss be pushing mph roughly?
 

Nealh

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At least 25km/h, unless the winding speed/ hub rpm is known we can't tell you anything else. With the hub rpm and wheel diameter we can calculate the approx. max speed.
 

Andy1865

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At least 25km/h, unless the winding speed/ hub rpm is known we can't tell you anything else. With the hub rpm and wheel diameter we can calculate the approx. max speed.
All i know Neal is that the wheel is 26"
 

Nealh

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So basically the U.K limit of 15.5mph
Yes, for a starters.
If the display allows de-restriction and the hub is a higher wound one then it will go faster. Unless the rpm is known we can't potentially tell you how fast.
 

Nealh

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The hub specs are 390 - 550rpm, depending which version is ordered/sent you can expect to see 23 - 42mph.
 

vfr400

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Motors have a fundamental characteristic called the Kv, which is how many volts per RPM it generates. The voltage it generates cancels out the battery voltage, so if you had a motor with a Kv of 0.184 it would generate 24v at 130 RPM, which is approximately 10 mph with a 26" wheel. If you have a 48v battery, at 260 rpm there is now 48v -24v=24v going into the motor to make power. When the motor spins at 260 rpm (20 mph), it's generating 48v, so you have 48v - 48v = 0v to power the motor. In other words, the motor will not be able to spin faster than 260 rpm with that battery, but if you gave it 72v, it would spin up to a maximum of 30 mph.

Hopefully, you can now see that the maximum speed of any motor is dependent on it's Kv and the voltage in the battery. Don't forget that the voltage of a 48v battery is 54v when fully charged and 40v when empty. Obviously, according to the above explanation, the motor's maximum speed will change in proportion, so you'd get 25 mph when charged and 16mph when empty.

Those speeds are maximum theoretical no load speed. There's one thing more to consider. When the motor is spinning at 250 rpm (19 mph) with a 48v battery, it'll be generating 0.184 x 250 = 46v, so you have 48v-46v = 2v left to power the motor, which isn't enough to get any meaningful power. It's enough to spin the wheel in the air, but not enough to drive you at 19 mph, so you'd slow down until you got to around 16 mph, where the net voltage would be high enough (10v) to push the maximum current theough the motor and give you enough power to maintain that speed.

To summarise, every motor has it's own Kv, which is fixed in the design by the designer, who can make it whatever he/she wants. If you don't know what a motor'sKv is, you can't determine how fast the motor will go. Sometimes the sellers will say 48v 260 rpm, which is enough, though they never seem to understand the importance of this information and they'll say something like 260 - 320 rpm. It can't be both. It's one or the other, but what they might mean is 260 rpm at 36v and 320 rpm at 48v.