How do I unlock the speed on this e-bike? Any help appreciated

[Bozolink]

Hello,
I recently bought this bike and I was wondering if there's any way to unlock the speed for it. I've attached pictures below but if any more information is needed please let me know. I have no idea about any of this so any tips or nudges in the right direction would be great. Thanks!

 

[glennb]

Nice bike. Serviceable battery, and fully accessorised with everything you need for year round riding.

No handlebar display?

Some experts will chime in to help you, and, if they have no direct experience with this specific bike, will likely want to know what controller it’s running.

The controller is likely enclosed in the boxy looking chamber lump behind/under the bottom bracket.

There’ll be a label on it that hopefully is the original manufacturer’s, and is hopefully facing toward the ground so that you can easily read it.

If either of those conditions is untrue, you might be required to rotate the controller to view the label, and, if Velectrix have relabelled the controller, even open it to see the manufacturer labelling on the PCB.

Worst case you simply (sic?) need to swap the controller for a different one. They only cost tens of dollars, although it can be bothersome to adapt plug and socket wiring to compatibiliise them.

 

[Bozolink]

Nice bike. Serviceable battery, and fully accessorised with everything you need for year round riding.

No handlebar display?

Some experts will chime in to help you, and, if they have no direct experience with this specific bike, will likely want to know what controller it’s running.

The controller is likely enclosed in the boxy looking chamber lump behind/under the bottom bracket.

There’ll be a label on it that hopefully is the original manufacturer’s, and is hopefully facing toward the ground so that you can easily read it.

If either of those conditions is untrue, you might be required to rotate the controller to view the label, and, if Velectrix have relabelled the controller, even open it to see the manufacturer labelling on the PCB.

Worst case you simply (sic?) need to swap the controller for a different one. They only cost tens of dollars, although it can be bothersome to adapt plug and socket wiring to compatibiliise them.

Thanks!
I've attached a picture of the handlebar display, and I've also attached a picture of the box the controller is housed in? I'll have to go pick up a hex screwdriver somewhere if I want to open it up.

 

[glennb]

You’re welcome.

Good photos.

It’s harmless to remove that cover - the controller is a separate box within that chamber, so there won’t be any springs flying out or seals to damage.

I’m going to go out on a limb and guess that the bike’s speed is being limited to 25km/h for legal compliance purposes. It is definitely capable of higher speed, but not necessarily higher enough to justify the effort involved in finding out.

It’s an over-simplification to say this, but how much higher largely depends on the specific motor. A photo of the manufacturer code on the motor will hopefully reveal this. You might need to look closely to see it … even a fine layer of dust could conceal it.

 

[Bozolink]

Where do I find the motor? Is this what you're talking about?

 

[Chalo]

If it's not beyond your ability, my advice is to substitute a generic 36V 22 amp controller. Get one along with a display if that's what you want, or a simple one that doesn't use a display if you only want full power throttle and/or full power PAS.

As glennb pointed out, this deal will probably require you to substitute some plugs and run some new cables. If you get a good photo of the plugs and label on your existing controller, we might be able to help you find one that won't need too much of that work.

It's unlikely, but possible, that your battery (specified as 36V 11Ah with Panasonic cells) will struggle to deliver 22 amps. If you're worried about it, use a 36V 15A controller.

 

[glennb]

So, you have a ShengYi motor.

Best guess DGW12MS, based on apparent diameter relative to the rear gear cluster.

You won’t find much info about them, but the bulky size indicates that it will handle plenty of power, and the single stage internal gear reduction suggests that it likely will spin up to higher speed at 36V. I believe it is a candidate for achieving higher speed with.

The speed signal will be coming from the motor, rather than an external magnet in the spokes. The plug from the motor will therefore have nine pins. You can unplug it check.

I have little experience with these plugs and can’t tell you what they’re called (9-pin juliet?) or which replacement controllers use mating connectors. Hopefully others can.

Your easiest upgrade path is getting the cover off, finding the controller model, and buying an unrestricted version of the same controller I.e. an otherwise identical one with same plugs that has not been crippled by a hardcoded speed limit.

This could include a more powerful controller by the same manufacturer.

It’s also entirely possible that a different controller manufacturer uses identical plugs, but you cannot be confident that the wires in the plugs are arranged compatibly with your motor.

Anyway, I’ll leave that to the controller and plug experts here to figure out. You’ll probably want to include photos of the motor plug to show them.

If you’re lucky it’ll be a kunteng controller in that box, which would make the upgrade super easy.

 

[docw009]

I would say that there's no power to unlock, unless the bike is restricted to 15.5km/hour.. If you get rid of that, you might go 30 km/hour. I've converted a half dozen or more bikes to electric using simialr sizw motors. They go about 30 -33 km/hour on 36V batteries and 20A controllers.

 

[glennb]

Indeed.

Hence saying “It is definitely capable of higher speed, but not necessarily higher enough to justify the effort involved in finding out.”

It can likely handle higher current than the stock controller permits though, it’s a chunky motor.

I’d be worthwhile hitting up European ebike forums for motor info, since shengyi are common there.