Author Topic: Replacing ignition with one toggle switch. Possible?  (Read 1938 times)

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Offline Gorms

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Replacing ignition with one toggle switch. Possible?
« on: October 10, 2009, 11:27:39 AM »
My '77 cb550k has the 5 wire ignition switch.  The 5th wire I think is for the parking light which I dont need.  If I recall, turning the key connects a red wire to a black wire (for engine power) and a brown wire to a white/brown wire (for the lights).  Can I replace the ignition switch with ONE toggle switch by soldering the red and the brown (havent checked but assume for now brown wire is positive lead for lights) to one wire of the toggle switch and solder the black and white/brown wires to the other end of the switch?  Or do I need 2 switches?  Thanks.

Offline Gordon

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #1 on: October 10, 2009, 11:32:14 AM »
Might as well do a separate switch for the headlight so you can turn it off when you need to. 

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #2 on: October 10, 2009, 12:37:01 PM »
A toggle switch will work, but to keep the tail-light working thru' it's own fuse ( the 7A one is the tail fuse) you will need a 2-pole switch, which is like 2 switches stuck together with one toggle. One pole would be black to red and the other would be brown to brown/white.
The description if buying one ( Radio Shack ? ) is D.P.S.T Toggle switch maybe 20A rated...........

Offline Gorms

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #3 on: October 10, 2009, 02:55:02 PM »
A toggle switch will work, but to keep the tail-light working thru' it's own fuse ( the 7A one is the tail fuse) you will need a 2-pole switch, which is like 2 switches stuck together with one toggle. One pole would be black to red and the other would be brown to brown/white.
The description if buying one ( Radio Shack ? ) is D.P.S.T Toggle switch maybe 20A rated...........

Thanks.  I saw these DPST switches and they have 6 contact points so I assumed that they would connect at least 2 circuits but the RadioShack dudes knew nothing about them, didnt know what DPST/SPST meant, and had no literature on the parts (typical).  Your comment about the taillight fuse:  I would only be messing with the wires at the ignition switch so I am safe right?

Offline celebutante

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #4 on: October 10, 2009, 04:19:49 PM »
SPST: single pole, single throw. Poles refer to the contacts, i.e. one set. It will have three contacts- the middle is common and the circuit is completed with either of the outer contacts depending on switch position.

DPST: dual pole, single throw. Six contacts, but it will basically have two separate cirtcuits like above, so the the two sets of wires going through are isolated- just like having two separate switches at once.

I wouldn't recommend buying switches (or any components for that matter) at Radio Shack- they're invariably junk, especially for a switch that will see a lot of use and outdoors, at that.

Best source would be Digi-key or Mouser online. NKK, Mountain are all good; in fact they don't sell anything that isn't good. Mouser will send you a huge catalog free. Both Mouser and Digi-key have great websites that let you see PDF's of the catalog pages, but it can be a little tricky to browse if you don't know exactly what you want.

Finally, pay close attention to the physical size and amperage rating as you'll want a pretty beefy switch for this application due to the current and wire sizes (i.e. you don't a miniature or sub-miniature toggle).

Offline Spanner 1

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #5 on: October 10, 2009, 09:58:23 PM »
2 contacts on a toggle switch = single pole, single throw = S.P.S.T.
3 contacts = single pole, double throw, where the switch is ' off' with the toggle centered and can contact 2 options ( seperately ) = S.P.D.T.
4 contacts ( usually ) is 2 pole, single throw, which is what you need to replace ign. switch, = D.P.S.T. A 6 contact switch will work with the center contacts and either end pair ( i.e. 1 pair will be unused ) = D.P.D.T.    any more letters than that, I'd see a Doctor....!!!

Offline Gorms

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #6 on: October 10, 2009, 10:27:57 PM »
Thanks for the clarification.  I just dont have room for my huge '77 ignition switch.  Might get a cheap smaller ignition switch from partsnmore later and locate it off a engine mount bolt but for now a toggle will work.  Not too worried about theft where I am.  Might mount a hidden kill switch under the cafe seat.  How would I do this?  What wire would I need to intersect that would be the easiest?

Offline Spanner 1

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #7 on: October 10, 2009, 10:37:20 PM »
Put a switch in line with the plain red wire from the starter solenoid........ this wire feeds the main fuse and on to the ign. switch.

Offline Gorms

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #8 on: October 10, 2009, 10:44:23 PM »
I seem to remember a yellow and maybe a black wire going to the solenoid but I could be wrong (maybe depends on the year).  Either way, thats a good idea.  Just got to keep the solenoid of actuating.

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Re: Replacing ignition with one toggle switch. Possible?
« Reply #9 on: October 10, 2009, 10:51:54 PM »
I mean the 2 big posts on top of the solenoid...the right-hand one has the big wire from the battery positive and a small red wire which carries power for all the bike ( +).......

 

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