Yosepower 350w 36v rear hub with 36v battery

Klang180

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Jun 6, 2017
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Hello

I have just finished a conversion for my partner of a nice hybrid bike with the YP 350w 36v rear hub kit. As my partner is only 55kg I thought the step down to a 36v wouldn't be too much of an issue but having taken it out I do think it is significantly less powerful than my 2 year old 48v version. I know this is to be expected but I wonder if there is any setting that might be restricting it at all or whether and upgrade of the controller might help? ObviouslyIMG_20210808_114143087_HDR.jpg 36v is 36v and so it might not be able to compete with the 48v I have but I know that she will be disappointed with the grunt provided so just checking if there is a setting I am missing or if anything can be done.
 

vfr400

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Jun 12, 2011
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Two things affect motor power - both in direct proportion. They're volts and amps. By power I mean torque, which is what you feel as power and need to get up hills. So, 48V gives 30% more than 36v and 18A gives 50% more than 12A, and 48v 18A gives 95% more than 36v 12A.
 
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Klang180

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Jun 6, 2017
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Two things affect motor power - both in direct proportion. They're volts and amps. By power I mean torque, which is what you feel as power and need to get up hills. So, 48V gives 30% more than 36v and 18A gives 50% more than 12A, and 48v 18A gives 95% more than 36v 12A.
Oh wow 95% more, that is crazy! So my affordable YP system is 36v 12A is a bit gutless and there is not much I can do about it. Better hope my partner is happy nonetheless, I am starting to realise I should have taken my time and got a better system, seems almost like £400 down the drain now. Yes a bit dramatic but ultimately a bit disheartened with only myself to blame.
 

vfr400

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Oh wow 95% more, that is crazy! So my affordable YP system is 36v 12A is a bit gutless and there is not much I can do about it. Better hope my partner is happy nonetheless, I am starting to realise I should have taken my time and got a better system, seems almost like £400 down the drain now. Yes a bit dramatic but ultimately a bit disheartened with only myself to blame.
The figures I gave are only examples and bear no relation to what you have. You have to look at the labels on the controllers to see what their max current is.
 

harrys

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Dec 1, 2016
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I recently bought a used Bafang BPM front motor and decided to use a Brainpower 10A controller on 36V to keep the power down, as it was front drive. Wow, was it gutless. I switched in a KT 10A square wave controller that had 20A peak, and the kick when applying throttle was back.

So you might make the best of it by putting in a somewhat bigger controller.
 
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Klang180

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Jun 6, 2017
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So this is the controller built into the mount I currently have. I guess it depends on what the battery can handle as well though but what are my options in terms of a better controller? If this one has a current of 9A and a max of 18A what can I push it too without compromising reliability (too much)?




controller.jpg
 

vfr400

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Disregard the 9A, It has no meaning. The 18A is how much current the controller will allow. Your battery can supply that, otherwise it would cut off. 18A is what most cheapo batteries can comfortably supply and is more than most. so that's not the reason that the motor feels gutless.

IIRC, there's a setting in the LCD that does something to the pedal asist. I think it feeds in the power slowly so that you don't get that horrible kick at start up, which you get from some speed control controllers. When I worked in a bike shop, the female customers would often be scared of that initial kick, on some bikes, and they would always buy ones that didn't have it. Blokes never seemed to mention it! I can't remember if those Yose ones have it, but if it does, you can adjust the start-up power in 5 levels. Download the LCD manual and go through the settings.
 
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Klang180

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Jun 6, 2017
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Disregard the 9A, It has no meaning. The 18A is how much current the controller will allow. Your battery can supply that, otherwise it would cut off. 18A is what most cheapo batteries can comfortably supply and is more than most. so that's not the reason that the motor feels gutless.

IIRC, there's a setting in the LCD that does something to the pedal asist. I think it feeds in the power slowly so that you don't get that horrible kick at start up, which you get from some speed control controllers. When I worked in a bike shop, the female customers would often be scared of that initial kick, on some bikes, and they would always buy ones that didn't have it. Blokes never seemed to mention it! I can't remember if those Yose ones have it, but if it does, you can adjust the start-up power in 5 levels. Download the LCD manual and go through the settings.
Thanks very much, it is time to download the LCD manual and get tinkering! Really useful info. It is for my partner (who is female) but unlike your experience I think she wants that punch from the hub so let's see if anything can be done about it.