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Increasing max speed and power via modifications

(my application is a Spectra HD 48V electric scooter and has a hub motor)
My scooter is from China and so when I got it it has a max speed limitation of 25kmh/ 15.5 mph. The place where I live has a 32 kmh/ 19.9 mph max speed limit for non licensed bikes.

The scooter is designed to run on a gas motor as an option and is built to be safely used at faster speeds. This scooter will be used on private property. I have heard that I might be able to add one more battery and convert this bike to 60v. I have heard that I might be able to modify my controller to allow this bike to achieve speeds beyond 25kmh.

My request for input is this: If I add the extra battery (I’ll need to find a place to stick it) without changing to a 60v controller, is there a chance it will work for a period of time and then burn out? What can I expect?


If the controller must be changed, does the controller and the motor need to be switched together as a team?


How much and which product do you recommend if I switch to a 60v controller and motor. Is the conversion fairly straight forward? Are there any special tools required?


Whether I do the volt increase or not, I am mostly interested in allowing this bike to move past the 25km/h pre-set limit. Can you guide me to a solution to increasing the speed of this bike?

Out of curiosity, how would modifying the 48v controller to a faster allowable speed change the over-all range of the bike AND how would changing the voltage to 60v change the over-all range.

Do you have any idea what the top speed of this bike would likely be in both voltages if there were no speed restriction on the controller?

Thanks in advance!

My request for input is this: If I add the extra battery (I’ll need to find a place to stick it) without changing to a 60v controller, is there a chance it will work for a period of time and then burn out? What can I expect? Some controllers can handle being overvolted and some can not. It may work indefinitely, it may immediately burn out or, or it may work for a period of time and then burn out.


If the controller must be changed, does the controller and the motor need to be switched together as a team? No they do not. You can  install a controller with a higher Voltage than the motor. The motor may run hotter than normal if a big enough load is put on it, so you would want to watch the temperature of the motor if you over Volt it.


How much and which product do you recommend if I switch to a 60v controller and motor. Is the conversion fairly straight forward? Are there any special tools required?  The controller depends on how many Watts the motor is and visa versa. I recommend using a controller and motor with the same Volts and Watts rating. Installing a different controller and motor could range from easy with no special tools needed, to difficult with modifications to the frame being necessary depending on the controller and motor that are being installed. 


Whether I do the volt increase or not, I am mostly interested in allowing this bike to move past the 25km/h pre-set limit. Can you guide me to a solution to increasing the speed of this bike?  It sounds like you are on the right path. I would start with a bigger battery pack and controller and take it from there.


Out of curiosity, how would modifying the 48v controller to a faster allowable speed change the over-all range of the bike AND how would changing the voltage to 60v change the over-all range.  The range of the bike depends on how many Amp hours the battery pack is rated for and how many Amps the motor and controller are drawing from the battery pack. The faster the vehicle goes the more power it will draw and the lower the range will be. I could not say for sure what the results of the modification will do the the range. You would have to try the modification first and then see what the new range is.


Do you have any idea what the top speed of this bike would likely be in both voltages if there were no speed restriction on the controller?  No I do not. I would expect an increase in top speed if you overvolted the controller and motor though.

Whether I do the volt increase or not, I am mostly interested in allowing this bike to move past the 25km/h pre-set limit. Can you guide me to a solution to increasing the speed of this bike? It sounds like you are on the right path. I would start with a bigger battery pack and controller and take it from there.


The right path is a far cry from faster speeds :)

 

1) Can I modify or adjust my current controller to acheive greater than 25 kmh speed?

2) Do the controllers that you sell (48v and/or 60v) have speed limits and if so can they be adjusted?

 

Unless your controller has a built in function to do so, I do not know of any way to modify or adjust a controller to make the motor go faster. Chances are that your existing controller does not have a speed limiter feature, but that the speed is being limited by the Voltage of the power source and maximum output Amperage parameter of the controller, thus the output Voltage and Amperage of the controller.


Our brushless speed controllers do not have speed limiters or adjustments to limit or increase the motors speed. Some of our brushed speed controllers do have power level adjustments though. With our speed controllers the motors speed will be limited only by the Voltage and Amperage that it receives from the controller. They do not have built in speed governors.


Brushless motor and controller systems often feel like they have speed governors because the motor will not turn faster than a certain RPM, however the speed is being governed by the Voltage of the power source and not the controller or motor.

Correct me if I'm wrong if you want more speed see if you can change your gear ratio to get more top speed

Changing to a higher gear ratio will increase the top speed of the scooter if the motor has enough power to propel the vehicle in the new higher gear. If the motor has enough power the higher gear will increase the speed, however if the motor is not powerful enough then a higher gear will make the scooter go slower.


For example a car with a 200 horsepower engine going uphill in 4th gear will start to slow down, but a car with a 350 horsepower engine will have enough power in 4th gear to accelerate up the same hill.

I buy electric scooter in 2015 1000w 36v with 3 batteries of 12v 50ah it's, I was used for 4 years til the batteries finish. Recently I disite to used again but because we have here (Crete) many mountains and became empty the batteries very fast from heaviness to buy half size batteries 26Ah. But I was wrong is weak and fall the volts rabidly in heals. So is possible to boost the motor when it falls to 36v from 41v when is fool the batteries with extra battery 6volt (8v fool) to become 44v to not stop the power the controller.??? This can happen only if the 6v battery is also 26ah? Or it doesn't matter?? Is anybody knows? Thanks....

The low Voltage cut off feature of the speed controller is there to protect the battery pack from being undercharged. If the speed controller allowed the battery pack to be undercharged that would damage the batteries and they would not last very long.


If a 6 Volt battery was added to the 36 Volt battery pack to increase its Voltage so the controller does not turn off when the battery pack Voltage is low that would keep the scooter running longer, however it would also allow the 36 Volt battery pack to drop into an undercharged state which would not be good for the batteries.


In your situation of needing more range the best thing to do, if there is enough space in the battery compartment, would be to add an extra three 12V 26Ah batteries to the scooter and wire them with the other three 12V 26Ah batteries is a series/parallel wiring arrangement to create a 36 Volt 52Ah battery pack.

What needs to not cut off the power in the hills, more volts or more capacity (bigger batteries) or more fat wires. Because after the hill don't have broblem make few km. more. And what if I put less than 26Ah 3 batteries parallel with the other 3 26Ah. For example the 3 26Ah with 3 10Ah they will be 36Ah all together bud this will solve my broblem with the hill? Because the hub wheel (motor) I m sure is enough strong to do it.

I recommend to load test the individual 12 Volt batteries in the pack because they should not drop Voltage like that under load. There may be one bad battery that is dropping too much Voltage under load and causing this problem. A good battery pack would not do what you are describing.


If an extra three batteries were added to the pack that were a different Ah rating then the original batteries then the smaller batteries would recharge faster than the larger batteries and their Voltages would become uneven which would damage all of the batteries due to over and under charging.


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