Question about kill switch.

Soliddrummer

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I am almost to the wiring stage of my bobber build, and am gathering bits. I've got the fuse block, starter solenoid, ignition switch etc. One thing I see recommended by lots of very knowledgable wiring guys on this site is to wire in a kill switch somewhere on or near the hand controls.

My question is, can the kill switch be any 2 wire switch? I'm using one of these for my starter, http://www.lowbrowcustoms.com/p2567...ersal/cycle-standard-mini-push-button-switch/ wired up to the right side of my bars, and was wondering if I could use another one as the kill switch, wired up to the left side bars.

As I understand it, the kill switch is wired between the battery and the ignition system, and pushing the button interrupts the flow of power to the ignition system, causing the bike to die. With this switch it seems to me, that pushing the button would ACTIVATE the switch, thus allowing power through to the ignition system, and allowing the bike to run. Do I need a switch that is in fact ALWAYS ON, and depressing the button TURNS IT OFF? Is there such a thing? Am I way off track here?
 
This is a push button, like a momentary start button, good for a start button or a horn button, I don't think it's what you need as a kill switch. You need a toggle switch, On and Off. I prefer placing the kill switch in line with the coil circuit, so it cuts power to the coil without shutting lights and anything else off. that is how I'm wiring kill switch, but you can place it everywhere you want...

edit: You need a relay for this switch, so it probably click at the bottom and the relay make it jump back, it might works as a kill switch w/o the relay... test it! Plug it in line with 1 wire on the coil...
 
Yeah, I guess I should have been more specific, when I say "ignition system" I mean coil. Hitting the kill switch interrupts power to the coil, thus shutting down the bike.

I guess I am asking if the "kill switch" is basically just a momentary off switch.

I'm seeing lots of switches on eBay that say "universal switch" for starter, horn, kill etc...so I can only deduce that depending on how it's wired in, any momentary switch could be used as a kill switch?!?!?!
 
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Yes, a momentary switch would work fine as long as it is normally closed and opens when you push it, killing power to the coil. Just remember you would need to hold it until it completely dies or it could take back off again. The switch you have a link to looks like a normally open/momentarily closed switch which would not work for that application.

Aaron
 
Think of it as a draw bridge over a river. Normally closed lets all the traffic across (power to your coil in this case) and when you want to raise the bridge and stop traffic (ie, kill power to the coils) you press it and it opens.
 
You can use a normally open switch for the kill switch if you wire it to the trigger side of the coil rather than the battery side.

I prefer this method since the power for the coil doesn't run through it while the engine is running. A dirty kill switch on the battery side will cause a bike to run poorly or not at all. Even a good switch will cause some voltage drop.

Putting the kill switch on the trigger side eliminates these troubles. A dirty kill switch on the trigger side will still kill the motor. Worse case scenario, the switch shorts out and prevents spark. Then you can simply unplug it and still get home.

Disclaimer; This type of kill switch can only be used to kill the engine. If you have a battery and leave the ignition switch on and kill switch in kill position then you will burn up the coil. A momentary switch would prevent this. A better solution is to wire the kill switch to the power side of the ignition module with a series resistor between the power and switch/module.
 
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Mrrigs, if I understand you correctly, a momentary normally open switch, wired into the non powered lead between the coil and ignition, will serve as a kill switch?
 
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