Electric Bikes - Sydney Hub Motor Sellers?

i am having trouble finding any suppliers around sydney selling hub motors or lithium type batteires,can anyone steer me to a good supplier?i need to change my toy currie 200 watt setup to something a bit more decent,the currie is a bit slow and doesnt like any hills,i might as well change the whole system to how it suits my riding.what is a good hub motor around the 350 watt mark running on 36 volts or 48 volts/

Hi Mike

Can I ask why 36V or 48V. I am curious on peoples understanding and perceptions on different system configurations.

thanks

well i have been told 36 volts or 48 volt systems give better speed and a bit more grunt,i am new at this but have done similar experiments with other smaller dc motors and more voltage does make them spin alot faster,like i said i am still learning so maybe you can tell me some more.

Hi Mike

Below is an extract from a typical motor supplier. I have removed other factors that will only confuse at this stage and have no impact on this discussion

The main point to rememebr here is that I am talking about motor selection for use as DESIGNED, not over volting, etc.

From the table it should become evident very quickly that an increase in operating voltage has no impact on speed. All that changes is the current, which is directly related to Volts.

So a 24V 350W motor has the same rpm as a 36V and 48V.
V rpm A W
350W24V 24 2250 ≤18.7 350
350W36V 36 2250 ≤12.5 350
350W48V 48 2250 ≤9.3 350
500W24V 24 2500 ≤26.7 500
500W36V 36 2500 ≤17.8 500
500W48V 48 2500 ≤13.4 500
750W36V 36 2800 ≤26.7 750
750W48V 48 2800 ≤20.0 750


Yoy will hear that people talk about over volting the motor. Well by all means do this but note a few things and to help think it through relate to a car motor under the same conditions.

By over volting the speed WILL increase, but the problem is that the motor's life will be shortened to start with. Next over volting will tend to saturated the core and over time will cause permanent magnitization, hence reduceing the effect. Next Torque does not increase in a linear relationship to the voltage increase (in this instance) and so to get the additonal torque desired the current increases. this causes excess heat, etc etc.

The MAIN benifit from increasing the DESIGNED voltage is that the required battery will require less current draw, so lower rated Ah and C batteries can be used. BUT, more cells are then needed, this increases the size and weight and normally reduces the options on where to place the battery pack.

With modern cells they are achieving better Ah and C rates. So there is a trend to consider going to 24V and then add smaller packs to increase range as thet can be loacted around the bike or for short runs less packs needed.

Hope this helps

Allan
www.elationebikes.com.au