Splitter for lighting?

anon4

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I want to install lights via the controller, most only come with 1 light output. Is there a splitter I can buy with the jst connectors so I can run both front and rear?
 

anotherkiwi

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b+m - rear light requires 6v
supernova - rear light requires 12v

Those are just examples, many wired rear lights are powered from the front light which provides the correct voltage. In my case the front light is spliced to the 44v battery wire and the rear light powered from the output on the headlight.
 

anon4

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b+m - rear light requires 6v
supernova - rear light requires 12v

Those are just examples, many wired rear lights are powered from the front light which provides the correct voltage. In my case the front light is spliced to the 44v battery wire and the rear light powered from the output on the headlight.
Ah so if I buy as a set that's how it works? Was just going to get a cheap "motorbike light" from eBay and this tail light: https://www.ebay.co.uk/itm/Electric-Bike-Scooter-Rear-Tail-Safety-Light-Warning-E-bike-Brake-Lamp-Universal/372522437762
 

anotherkiwi

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Your rear light says Working Voltage: 6-80V so it must have a buck converter inside. I never got around to making a pretty light cable, I just soldered to the main cable on the controller.

If you are thinking of using the 6v out from the controller so that you can turn the lights on and off from the controller you will find it is pretty feeble and often limited to 2 or 3 W. In my case the battery is on, the lights are on - I find that riding with the lights on 24/24 helps motorists judge your speed better.
 

anon4

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Your rear light says Working Voltage: 6-80V so it must have a buck converter inside. I never got around to making a pretty light cable, I just soldered to the main cable on the controller.

If you are thinking of using the 6v out from the controller so that you can turn the lights on and off from the controller you will find it is pretty feeble and often limited to 2 or 3 W. In my case the battery is on, the lights are on - I find that riding with the lights on 24/24 helps motorists judge your speed better.
I thought the light output on controllers was normally set at battery voltage, hence the need for lights with buck converter? At any rate the main reason I'm wanting to do this is my rear light keeps dying without me realising, if I have them hardwired this won't happen. I can still run a usb headlight if the built in one is weak for unlit areas
 

anotherkiwi

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I thought the light output on controllers was normally set at battery voltage, hence the need for lights with buck converter? At any rate the main reason I'm wanting to do this is my rear light keeps dying without me realising, if I have them hardwired this won't happen. I can still run a usb headlight if the built in one is weak for unlit areas
Yes but the current is very low on KT controllers for example, it is just a relay switch. Bafang controllers are 6v/3W.

https://endless-sphere.com/forums/viewtopic.php?f=2&t=79763
 

vfr400

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That connector will work OK for a LED back light.

If you choose one with low power, you can add a low power front light too.

If you look inside the controller, you'll most likely see that the transistor that switches the wire is tiny. On some controllers, when that transister blows, it takes out the whole controller, so you need to be careful.

Get the markings off the transistor, then you can find its exact rating from its data sheet.

To join the back and front lights, there's no need for a connector. Just cut off what's on the controller and wire them in parallel directly. If ever you need to change anything, it's a lot quicker and easier to cut the wires and resolder than it is to solder on connectors. It also gives you a more reliable and more efficient connection.
 
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anon4

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That connector will work OK for a LED back light.

If you choose one with low power, you can add a low power front light too.

If you look inside the controller, you'll most likely see that the transistor that switches the wire is tiny. On some controllers, when that transister blows, it takes out the whole controller, so you need to be careful.

Get the markings off the transistor, then you can find its exact rating from its data sheet.

To join the back and front lights, there's no need for a connector. Just cut off what's on the controller and wire them in parallel directly. If ever you need to change anything, it's a lot quicker and easier to cut the wires and resolder than it is to solder on connectors. It also gives you a more reliable and more efficient connection.
Was going to use one of these or is it too powerful? https://www.ebay.co.uk/itm/High-Power-Motorbike-E-Bike-12V-24V-36V-48V-80V-LED-Spot-Light-Headlight-New/153387150608?_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=20160908105057&meid=0db0931544eb4b6985cfb1c0938312bc&pid=100675&rk=1&rkt=15&sd=153387150608&itm=153387150608&_trksid=p2481888.c100675.m4236&_trkparms=pageci:a3f0edfe-44ac-11e9-8292-74dbd18012a1|parentrq:7151ee491690a86017589212fff071a9|iid:1
 

anon4

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What I might do instead is use the controller plug for the rear then splice a front with horn and switch to the battery itself
 

Woosh

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Was going to use one of these or is it too powerful?
https://i.ebayimg.com/images/g/hTsAAOSwJrdcbRx6/s-l1600.jpg

look how flimsy the wires are. Imagine you connect your battery's output directly to them. It won't take much for an accident to happen. The light switch on the LCD, the 1-4 trunk cable, the controller and battery's protection circuit can all be fried.

Don't do it.
If you absolutely want to feed your lights from the main battery, get a converter and install it inside the battery so it acts as a fuse.
 

anon4

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https://i.ebayimg.com/images/g/hTsAAOSwJrdcbRx6/s-l1600.jpg

look how flimsy the wires are. Imagine you connect your battery's output directly to them. It won't take much for an accident to happen. The light switch on the LCD, the 1-4 trunk cable, the controller and battery's protection circuit can all be fried.

Don't do it.
If you absolutely want to feed your lights from the main battery, get a converter and install it inside the battery so it acts as a fuse.
So is it safer from the controller lines then? I had a display wire short once, the smoke coming off it was incredible!
 

Woosh

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So is it safer from the controller lines then? I had a display wire short once, the smoke coming off it was incredible!
I used to have main battery powered lights on the old Sirocco. The rear light is directly on the rack battery, the 6V converter is installed inside the controller box. The cables got snagged fairly often, but the converter can deal with short circuits by itself.
Still, it's just not worth the saving on a rechargeable front light. I paid $10 for the USB rechargeable torch with 3 Cree LEDs.
http://wooshbikes.co.uk/?sirocco
 

anon4

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I used to have main battery powered lights on the old Sirocco. The rear light is directly on the rack battery, the 6V converter is installed inside the controller box. The cables got snagged fairly often, but the converter can deal with short circuits by itself.
Still, it's just not worth the saving on a rechargeable front light. I paid $10 for the USB rechargeable torch with 3 Cree LEDs.
http://wooshbikes.co.uk/?sirocco
I use usb lights now but I'm tired of the endless charging. Surely there's a working solution?
 

Woosh

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May 19, 2012
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I use usb lights now but I'm tired of the endless charging. Surely there's a working solution?
have a battery with usb charging socket, connect your light USB to the battery USB.
 

anon4

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have a battery with usb charging socket, connect your light USB to the battery USB.
Hmm mine has a socket but it hasn't been wired in by pswpower. Think you can buy the board on AliExpress but not sure how you go about installing it
 

Woosh

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Hmm mine has a socket but it hasn't been wired in by pswpower. Think you can buy the board on AliExpress but not sure how you go about installing it
it's quite simple, connect the two wires red and black to red (36V) and black (ground).
 

Nealh

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With the Big Bear kit I use a pair of Banggood 6-80v lights and simply paralleled them & connected to the main power wires from /to the controller with a switch and fuse on v+ side of the lights.


With the KT controller I use a KT combi horn/light simply wired them direct to the light output with the KT light/horn switch, the rear light is still a 6 - 80v Banggood one. Light switch is the same type as VFR has linked to.
 

anon4

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With the Big Bear kit I use a pair of Banggood 6-80v lights and simply paralleled them & connected to the main power wires from /to the controller with a switch and fuse on v+ side of the lights.


With the KT controller I use a KT combi horn/light simply wired them direct to the light output with the KT light/horn switch, the rear light is still a 6 - 80v Banggood one. Light switch is the same type as VFR has linked to.
Could you link me the KT light/horn? Is the rear light still wired direct to battery?