Help with LED Bar light and switch on bike

[Parmenter]

Thanks for looking.
This question is not boat related though I will be installing some of these LED bar lights on the boat at a later stage and I figured there are more 12v experts here than just about anywhere on the web.

I need some extra low beam light on my motorbike as the 35w bulbs are as bright as a torch with a flat battery and brighter hotter bulbs apparently melt the plastic of the lens.
The cheapest and probably easiest option is to install an LED bar light like this and there are various videos on youtube confirming their effectiveness for this use.
and have it angled down so it only lights up directly in front and no further than the low beam reach.

Law in Australia says it must be on high beam, on with high and off with high so I want to be able to demonstrate that if required but I really only need it on low beam so want to rig a sneaky switch in the glovebox.

Can someone please confirm if I have this right, forget about legalities of it please, just want to know if it will work.
It is only 18w so I was hoping not to need relays and that a splicing into low and high beam power and a simple switch and inline fuse would work.



Its sort of an opposite to this

https://www.youtube.com/watch?v=y2-d_9GkCb4

[Parmenter]

No one?

Its in bits now, wire cutters at the ready, waiting for someone to give me the nod or not.

[Paul Elliott]

This should work, but why don't you put the fuse between the switch and the LED bar? I don't like fusing the ground lead.

[Parmenter]

Originally Posted by Paul Elliott

This should work, but why don't you put the fuse between the switch and the LED bar? I don't like fusing the ground lead.

Thanks for the reply Paul

So 2 fuses?
One on high beam wire and one on low beam wire?
I could do that, figured one on earth would achieve same.
Any reason why I cant do that?

It did all work to plan, I haven't put the fairings back on yet so I can easily get a 2nd in line fuse in the morning.

[sparrowhawk1]

The Schematic shows only the positive wire.( it goes through the LED so maybe technically it's poss and negative for the LED) What you show has it on whenever the headlights on, either high or low. The video is correct as far as the terminals and which way the switch is pushed

[Paul Elliott]

The fuses should protect the wire. You already presumably have a fuse or two in the headlamp feed(s). If these are appropriately sized for the LED wiring as well, then you don't need an additional fuse. If your LED wiring is too small for the fuse(s) then you will want the LED fuse. It really doesn't matter if the fuse is in the positive or negative wire, but I prefer to have it in the positive as a matter of convention. If it's easier to put it in the negative lead than that's OK too, as long as you remember where you put it.

The way the switch will function is this:

Lights off -> LED off
High and/or Low Beam on -> LED off when switch is centered (OFF)
High Beam on -> LED on when switch is up (ON)
Low Beam on -> LED on when switch is down (ON)

[kentobin]

Your light bar will already be fused through your hi or low beam fuses. If you put in a second lower amperage fuse in series it might blow before the other light fuses but sounds more like a situation of Russian roulette. It may work but it wouldn't be my feel good choice.

Also depending on the current draw of the new light bar your current fuses to your hi or low beam may not be high enough to run the light bar too. If that is the case you'll need to connect the light bar to a relay. The relay gets turned on and off by the switch as you already posted. Then connect one side of the relay directly to the battery and fused and the other lead run to the light bar.

As already mentioned it is best NOT to fuse on the ground wire. The rule of thumb is to get the fuse as close to the battery as possible within reason.

[GrahamHO]

I also don't see the need for the fuse as the main headlights must already be fused. You can work out whether the existing fuse is OK by adding the total amps when all is on. If the existing fuse is too small, DONT uprate the fuse as the wiring may not be suitable for the higher current. Allow some reserve and perhaps use a "slow blow" fuse. The only problem I see is that going from H to L (or the other way) there is an off in the middle which might accidentally be selected when changing. I have a similar switch in my boat for a different purpose with no off in the middle. It snaps across from one position to the other and has a chrome toggle with a red "on" label either side. It looks better quality than the one in the video. I bought it from a JAYCAR store in NZ. Every town in Australia has a JAYCAR and their staff are very helpful with advise if asked. If you want an "off" position you could have a second "on / off " switch where you show a fuse.

[Parmenter]

OK, so existing lights being fused makes sense and checked wiring diagram from manual to confirm this.
Did the install and all works fine,
I didn't use a switch like in the video but instead used a toggle with waterproof boot.
Went for a ride last night coming onto dusk and about an hour longer on roads with a fair bit of traffic and now I can see.
The area directly in front and to the sides where the low beam barely lit is now white and no cars flashed their lights, so its obviously not blinding anyone.

Thanks all who contributed