Help with finding speed box for my e-bike

[nippleripple2]

Hello, I’m new here, but excited to be here. I could really use some help as I’m not very smart when it comes to ebikes, an electrical motors. I’m have read about people getting a speed box or a tuning chip/box for the bike that actually allows them to go faster and or control more of the bike settings specifically for gaining speed. I have a 750 W 48v 30ah romatlink folding e-bike I have tried looking at the controller to see if I could find anything specifically for the model that I have, but I’m having trouble doing so please if anybody has any information I would be so grateful as I’m not so worried about the length my battery lasts or the distance that I go necessarily however I do specifically need to go faster if it all possible I’d like to try and do so without having to buy a new bike.

 

[alihyder]

I totally get what you’re saying, digging into e-bike tuning can feel a bit overwhelming at first. I’ve been through that rabbit hole myself. With a 750W 48V setup like yours, you’ve got a strong base, and yeah, unlocking more speed is often possible. A lot of bikes have speed limits set in the controller or display menu, so sometimes just accessing hidden settings can help (usually by pressing a combo like "+" and "–"). If that doesn’t do it, a tuning chip or speed box might work, but you’d need to know the controller model to find one that fits. It’s doable without getting a new bike, just take it one step at a time.

 

[nippleripple2]

Yes, I tried to adjust the settings through the manual mode, pressing + - but but honestly, I didn’t do anything mostly different at all, and I have a picture attached of my controller. Do you have any info on a possible speed box of some sort for that type of controller?

 

[alihyder]

Your e-bike has a 48V controller made by Dongguan Dayrui, which is pretty common. These controllers don’t always work with speed tuning chips, but you still have some things you can try. Since pressing the “+” and “–” buttons didn’t change anything, check your display for hidden settings (like P or C settings) that might unlock higher speed limits. If that doesn’t work, you might want to think about changing to a more tuning-friendly controller like a KT controller, which is easier to adjust.

 

[nippleripple2]

Or what if I clip the white wire from the controller ( I’ve heard this is the wire for the speed limiter) would cutting this wire and grounding it do anything.

 

[Chargeride]

What speed it it restricted to, a 30A controller should easily do 30mph, but you are on 20 inch tires, you might simply be reaching the max speed of the geared hub.

 

[alihyder]

Cutting the white wire might remove the speed limit, but it depends on your controller. Some bikes use that wire to control the speed limiter, so it could work, but there’s also a chance it won’t do anything or could cause an error. Since your controller isn’t the easiest to modify, it’s a bit of a gamble. If you try it, do it carefully and be ready to undo it if something goes wrong. If you want a safer option, switching to a controller like a KT model (which is easier to adjust) might be a better choice in the long run.

 

[nippleripple2]

What about this controller would this one be better or possibly something that I could adjust in the settings a little bit more so what I’m capable of doing now(I do have the LCD that comes with it as well. I’m wondering if I could just swap them out since I think they have exactly the same plugs

 

[Slaphappygamer]

That white wire, does that have a connector on it? The speed limiter wire is usually a single wire connected to itself. You shouldn’t have to cut anything.

You could replace the controller and display, assuming they work. Even though the connectors look the same, you MAY have to realign the wires in the connector.

This video shows a bit how to remove the pins. Then you can reinstall them in the configuration you need.