Help Needed with low power bike.

[iceeci]

Hi All,
I need some advice on my new controller and motor.
Recently i changed a new motor and controller for better pick up and max speed but had an issue when my battery reaches 48v. ( its all well and fast after a charge )
( Every method or issues occur - with or without regen braking, speed 1 to 3 etc )
The bike would not have much pick up at 48v max speed seems to be 15km/hr )
Pas turns off when bike reaches the sad max speed.

Bike Spec:
( 2015 march batteries ) 48v( 4 x 12v ) 12ah sla battery ( planned to get life battery after this dies off )
48v 500w 12 mosfet sine wave 30A 120 degree hall sensor controller. Low volt 42v max volt 65v.
18inches 350w 500 rpm
bike weight approx 50kg with battery and rider and pillion approx 150kg

My previous bike:
48v( 4 x 12v ) 12ah sla battery
48V 350w 9 mosfet 19A 120 Degree hall sensor controller.
18 Inches 200w ???Rpm.

From what i know sla battery will loss it power when it hits 45v but now i am loosing power when it reaches 48v.

Please help and advice me what is the possible problem as the seller claimed it never happen before and local vendor will suck my blood suggesting to change whole set for approx 800usd.

Many Thanks In Advance, :wink:
IceecI

 

[d8veh]

This has come up a few times before. I'm going to take a wild guess that it's a KT controller that has the 5-pin connector for the LCD with the red and blue wires shorted., in which case you need to get the LCD.

 

[iceeci]

This has come up a few times before. I'm going to take a wild guess that it's a KT controller that has the 5-pin connector for the LCD with the red and blue wires shorted., in which case you need to get the LCD.

My controler is for led not lcd so i do not have those 5 in 1 connector wires .
do you sharing with me the links as i couldn't find them.
Thanks

 

[amberwolf]

What voltage do you read with a multimeter/voltmeter across each of the 12v batteries while under load when it cuts out?

 

[iceeci]

What voltage do you read with a multimeter/voltmeter across each of the 12v batteries while under load when it cuts out?

It is sometimes 11.8 to 12v per battery.

The weird thing is that when i place the bike on the stand the wheel move but at a slower speed than full charge. But when load is on it, the bike would jumped approx 3 times and move slowly.

Any suggestion what is the issue?

 

[d8veh]

If you have the 4-wire LED panel connector, what I said before doesn't apply, but your speed will be limited to level 1 of 3 for PAS operation if you don't connect the control panel. Throttle would work normally. The speed signal wire (normally green) gives 1v for level 1, 2v for level 2 and 3v for level 3.

 

[iceeci]

If you have the 4-wire LED panel connector, what I said before doesn't apply, but your speed will be limited to level 1 of 3 for PAS operation if you don't connect the control panel. Throttle would work normally. The speed signal wire (normally green) gives 1v for level 1, 2v for level 2 and 3v for level 3.

I understand where you are coming from. I do not have this function on my controller. But have a 3 speed wire. I did tried all 3 speed when my bike loss power at 48v, it doesn't seems to have much difference.

Do you guys thing is the 12 mosfet 30a controller is too powerful for my sla 48v 12ah battery?

 

[iceeci]

Just an update from the seller.
Suzhou SND Zhenlong Motor Co. Ltd from aliexpress.

Kevin told me

2015-06-30 19:49:53
Hi Lee,
This motor make faster speed,and also it need more power to run with it. ( It is just 150w more than my old motor )
our controller limit current is 30A,when the battery voltage is higher,it works ok. ( Its common sense that it will work faster due to higher v and slower when v drop )

but when the battery power become lower,the battery current maybe can not satisfy with the motor,so the speed will become slow .(one more things need notice,the sine wave contrller will detect the battery voltage and current,when it detect the battery voltage or current can not insufficient ,it will adjust the speed to save the power,so that the e-bike can run rest power for more distance. ) ( is there such thing for sine wave or only their company sine wave will cut down on power? )

About the PAS,it is not say it do not work,i think when starting at the 48V,the motor need more current to start,but the battery can not provide so much current ,so it seems that it can not work,acculately it works. ( Is what he saying true? i will be getting a multimeter and test this pas and his not function wires. Any advice how or what volt the reading should be? )
If you think it is not good for your e-bike,ok,we can exchange the controller for you.
Make it low power for it.

IN the first place i have told this seller my battery is 48v 12ah sla battery and yet he unprofessionally recommended me this motor and controller and claimed it will work fine with my battery.

Any advice on this for me?