Honda VTX Forum banner
1 - 3 of 3 Posts

·
Registered
Joined
·
6,253 Posts
If that switch is burnt then you absolutely have something wired wrong.
if you have accessory highway lights or something that draws a lot of power (radio) connected to the wires in the headlight bucket that is why it burnt up. Do not connect any accessories to the bike wiring . All accessories should have a seperate wire running from the battery threw a relay.
If you just replace the switch it will burn up again.

Donut
 

·
Registered
Joined
·
6,253 Posts
the switch issue isnt just people adding stuff. i dont have any extras and mine melted
Greg, thats surprising to here. All of the ones I have delt with in the past have been caused because of the accessories connected to the wiring in the healight bucket. There is not that much current going threw that circuit to burn up the switch unless there is a short omewhere. I'm guessing. So that really puzzles me.
Anyway the seperate hotwire off the battery threw a relay is the safest way to go.

Doug
 

·
Registered
Joined
·
6,253 Posts
Those statements are just wrong. Blanket statements like that usually are. THE ONLY thing going thru the switch is the headlight power line, so unless you wire into the headlight power any other wires in the bucket are not going to affect the switch operation. Nothing else goes out other than the headlight when you hit the switch so therefore nothing else is going thru the switch. Just look at the electrical diagram its only the headlight power. In addition, the headlight power line is fused at 10A, I don't know of anyone that adds directly to the headlight line and also ups the fuse to compensate for the addition. That switch is on a 10A fused line so by safety design standards the switch would be required to handle at least 10A.

The issue is cycles. Everything electro/mechanical has a life cycle. Everyone knows when you throw a switch you get a little arc, a light switch at home, an electric drill, just disconnect the battery in the dark and touch the terminal with the cable and even the odo holding current will give a little snap. You do this enough times at several amps and the surface of the connection erodes away, continuing the surface erosion you end up with a smaller conduction path, at some point the surface area can't handle the current and now you have excess heat caused by the resistance, current trying to conduct thru too small of an available path.

Regarding the relays, not everything requires a relay which is why many electrical accessories don't have them. It all comes down to what end function you desire and then design it soundly to meet that function. Other than the engine electrical requirements everything else is considered an electrical accessory on a vehicle. For example our horn works absolutely perfectly without a relay, but a lot of vehicles have a horn relay, put a stebel on an x and it is a good idea to do it through the relay. Why doesn't our horn have a relay? because the horn switch is adequate to handle the current of our little squeaker so a relay is not required. Stebel startup current is pretty high so you don't want to run it thru the stock switch.

I could give a lot of examples where a relay is desirable and where it isn't. For simplicity a relay is a switch and in automotive uses its primary purpose is to act as a switch, either as the main switch or to protect (bypass) a smaller switch. If you don't want/need it switched or the existing switch is adequate in size then a relay is not needed.

A CB radio for example. I wouldn't want that switched through a relay because I want to be able to still use it if I'm broke down on the side of the road without turning the key on. And it doesn't need another switch since it already has its own correct rated switch built in. Similar with my accessory power port, I don't want it switched because I plug the tender in there, I've used it a few times with my air compressor for flats, and I run my computer through an inverter off it when I'm in the tent. It is direct fused to battery.
There has been many, many,many in the past that have burnt that switch up in the past from adding accessories by connecting into power in the headlight bucket and that is why I strongly encourage everyone to run a seperate Hotwireoff the battery triggered by a relay.
The bike wiring is just not capable of handling a bigger load.
 
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top