Cannot undo speed restriction

[fededamiano]

Hello -

My ebike has an s830 LCD display and is speed limited to 33.8 kmh (regardless of including a higher value in the P08 setting).

The controller is as per the pic attached.

I have opened the controller and there does not seem to be any cable looping back to the controller (ie. speed limit cable) however it is hard to see as the cables are bundled into group connectors (rather than other DIYs I ve seen where each set of cables are separate).

Any hints on how I may be able to overcome the speed restriction?

Thanks in advance

 

[E-HP]

Hello -

My ebike has an s830 LCD display and is speed limited to 33.8 kmh (regardless of including a higher value in the P08 setting).

The controller is as per the pic attached.

I have opened the controller and there does not seem to be any cable looping back to the controller (ie. speed limit cable) however it is hard to see as the cables are bundled into group connectors (rather than other DIYs I ve seen where each set of cables are separate).

Any hints on how I may be able to overcome the speed restriction?

Thanks in advance

View attachment 341870

What leads you to believe there is a speed restriction?

 

[Hootz]

What do you currently have P08 set at?

 

[fededamiano]

What leads you to believe there is a speed restriction?

Thanks - a few things:
*Motor assitance switches off at that speed.
*Using the throttle speed caps at that speed and using pedal assist only also caps at that speed (unless I pedal very hard)
*Ebike manual says that changes to P08 above 25 kmh are inconsequential as it is factory limited above that (not clear whether the LCD or controller and also a not accurate as does allow to go a bit beyond that)

For reference, it is a 'Valk' brand ebike.

 

[fededamiano]

What do you currently have P08 set at?

Thanks. Currently at 40 kmh but have also tried at 50 and 100 (as per advice in different forums) with no change in max speed.

 

[E-HP]

Thanks - a few things:
*Motor assitance switches off at that speed.
*Using the throttle speed caps at that speed and using pedal assist only also caps at that speed (unless I pedal very hard)
*Ebike manual says that changes to P08 above 25 kmh are inconsequential as it is factory limited above that (not clear whether the LCD or controller and also a not accurate as does allow to go a bit beyond that)

For reference, it is a 'Valk' brand ebike.

Whether there's a limit or not, you're right up around as fast as 36V/20A will take you. You may be able to eek out another 2kmh. Did you test with the wheel off the ground?

 

[fededamiano]

Whether there's a limit or not, you're right up around as fast as 36V/20A will take you. You may be able to eek out another 2kmh. Did you test with the wheel off the ground?

Thanks - yes I did.

Someone advised I re-test with full battery and closer to empty battery to see whether it is a power restriction or a controller restriction. Havent done this yet, will do.

 

[E-HP]

Thanks - yes I did.

Someone advised I re-test with full battery and closer to empty battery to see whether it is a power restriction or a controller restriction. Havent done this yet, will do.

If the speed is the same with the wheel off the ground, then it's the controller limiting the speed.

 

[fededamiano]

If the speed is the same with the wheel off the ground, then it's the controller limiting the speed.

Thanks, I miss understood. The speed I referred to above was with the wheel off. When riding on flats it caps at ~ 2 kmh less (33.8 vs 31.2 kmh).

Is there a way to crack the controller? (happy to do some reading, just looking to be guided in a direction)

Thanks again

 

[amberwolf]

If the speed is less when on ground than off ground, the controller isn't limiting the speed, the system voltage and/or current and/or motor winding is.

If the controller was limiting, it would be identical speed off ground or on.


If the controller actually turns the motor off once it reaches a certain speed, then yes, it is limiting...but since you are getting a lower speed when it's loaded, it means that there isn't enough power to go as fast as the unloaded limited speed.

Does it do the same speed on a hill as it does on the flat ground?



However, if you can change limits in the display and it doens't affect it, then either the controller is not doing "speed" limiting, but is instead doing "power" or "current" limiting, or the controller is programmed not to respond to changes above some limit, and you would probably have to replace it with a new one to change that--these are not usually user-programmable to change that.



I suspect that you need either a higher voltage battery (along with a controller to match), a higher current controller (along with a battery that can supply that current), or both.

 

[fededamiano]

If the speed is less when on ground than off ground, the controller isn't limiting the speed, the system voltage and/or current and/or motor winding is.

If the controller was limiting, it would be identical speed off ground or on.


If the controller actually turns the motor off once it reaches a certain speed, then yes, it is limiting...but since you are getting a lower speed when it's loaded, it means that there isn't enough power to go as fast as the unloaded limited speed.

Does it do the same speed on a hill as it does on the flat ground?



However, if you can change limits in the display and it doens't affect it, then either the controller is not doing "speed" limiting, but is instead doing "power" or "current" limiting, or the controller is programmed not to respond to changes above some limit, and you would probably have to replace it with a new one to change that--these are not usually user-programmable to change that.



I suspect that you need either a higher voltage battery (along with a controller to match), a higher current controller (along with a battery that can supply that current), or both.

Thanks.

Current

 

[fededamiano]

Thank you all.


I did some tests and also asked the shop I intend to take the ebike for service (who has experience with this make).

the limiting factor is the motor windinds.

 

[Chalo]

the limiting factor is the motor windinds.

The limiting factor that you can change more easily is the battery voltage.

Most, not all, 36V controllers will operate on 48V. Using a 48V battery would increase your free speed by 30% and your road speed by something less than that, maybe 20%.

 

[fededamiano]

The limiting factor that you can change more easily is the battery voltage.

Most, not all, 36V controllers will operate on 48V. Using a 48V battery would increase your free speed by 30% and your road speed by something less than that, maybe 20%.

Thank you