Chef needs momentary switch related

Thread Starter


Joined Mar 26, 2007
Hi there, I am new to this sight and am I ever glad I found it.

Here is my project. I have a motorcycle that used to have some switches that I replaced with momentary switches. Understand that these new switches came as part of new hand controls for my bike.

Here are three problems.

1) I want my signal lights to stay on when I push the button. Is it a relay I need to install?, or is it a latching switch/relay? The momentary switch would have to trigger something so it stays on. If it is a relay I need, can I use 1 relay for both signals seeing as they do not turn on together?

2) High beam also only stays on while depressed. Should have lobeam all the time and then push the switch for high beam. I guess same problem as above.

3) Engine kill switch and starter button. Kill switch had an on/off position and the starter button only activates when kill switch is in the on position. Can I wire these so that if I push 1 button, it will both turn the kill switch on and trigger the starter button? That way I can use the last momentary switch as the kill button.

Right now I have the kill switch on one button and the starter button as another. I have to depress both buttons to start and I am left w/ no kill switch.

Please help


Joined Mar 22, 2007
Hi Chef

I'm having some trouble understanding what the problem is here.
So you replaced 'some' switches with momentary switches.
Firstly we would need to know what the switch type was that you took off, as this will help in, what I think you're trying to do, converting the momentary switch into the original type of switch?

The easiest solution I can think of is buy the right switches for the job! :p

But as the question has been asked I guess to fully answer we will need to know how many functions you intend to use with how many switches.

And when you say you push the button, do you mean push and hold, or push and release?

Also, have you tried some 'motorbike of your type' forums? I would have guessed you are not the first person to try this?

Thread Starter


Joined Mar 26, 2007
Hey Dave, thanks for replying. I'll try to keep this as short as possible. I bought a new set of mastercylinders for my motorcycle that came with control buttons. Those buttons are momentary in that they only work while you are holdong them in. They need to work like the stock ones did so that they stay on after you release the button. Here is a relevant example. There is an engine kill switch which is either on or off. That switch needs to be in the ON position for the bike to start and must remain in the on position to keep the engine running or it will kill the engine. Now that new button is a normally off press for on button. I have looked for a suitable replacement set of buttons or a switch, but none fit in the tiny holes in the control housing.

I have a couple of options here, one is to get a normally on push for off momentary button except that it would also need to accept the cap that goes over all the buttons. That would work fine if I could keep the cosmetics looking sharp, that's why I bought these controls.

Option 2 is that I could splice the kill switch wires into the ignition so that when I turned the key on, the kill switch would turn on at the same time. NOT the safest thing to do, imagine an accident happening pinning you under the machine with the gears still engaged, the rear tire would continue to spin as long as the engine is running which could possibly shred me into little peices. If a kill switch existed a simple flick of the switch and the engine stops. The ignition key is located under the drivers left leg.

Option three
which would be the best option as I also need to work a similar switch for my headlight, is to build a circuit that keeps the voltage alive in the system. I have found several such devices, some made with 555 timers, capacitors and resistors, then others w/ transistors, capacitors and resistors.

I purchased the modules to make a 555 controlled circuit that was supposed to allow this to happen. So far, I have not been able to get the circuit to function properly.

Now, here are the functions I would like to be able to do from the momentary buttons, and remember, there are no switches available in a size as miniature as I need them, so I have no choice but to "rig" something up.

1) Kill switch ~a switch that can be either on or off but must stay in the on position to run the bike

2) Highbeam switch~ same situation, when I push the button I need it to stay on. The momentary switch works only while I am pressing it.

Both the kill switch and the hibeam switch have to be able to stay on or stay off.

3) signal buttons~ this one is not absolutely necessary, however, I would like for them to work off of timed 555 timers so that they only stay on for 30 seconds. I don't mind holding those in to turn and I kind of like the idea of never forgetting them on so either way, momentary is fine, timed would be better. Another option would be the same as the devices on the market for motorcycle signal cancelling, and those work off of I think mercury balance switches. When you lean to turn, the mercury travels to the switch and cancels out the signal.

I am a member of a motorcycle website and posted the question there as well but as of yet, no cure.

Here is a diagram of a switch circuit that is supposed to do the trick, but like I said, I can't get it to work properly just yet. I can't get it to stay on and when I do get it to stay on, it won't turn Also, I have been able to make a cuircuit that enables the momentary button to work like a momentary

Here are the switches and housing

and here is the 555 circuit


Joined Mar 22, 2007
Safety is paramount, so that drops option 2 out of the window!!

Ok, I can just about visualise the solution theoretically, however, I have no clue how to implement it practically!

Your Kill switch and High beam switch could be implemented on separate Finite State Machines. These would have 4 states.
A: Input 0. Output - Turn Light On.
B: Input 1. Output - Nothing
C: Input 0. Output - Turn Light off.
D: Input 1. Output - Nothing.

So you can see the loop there of light being on, and then when you press the button down, and release again, that counts as 2 states.

Now you can use a latching circuit which doesn't need a clock input. I did a quick search around and can't find anything suitable. I've never done anything like this before so hopefully another forum member will easily spot the IC you need for the job.

As for the signal L/R switch. Do you only have one switch for this? Also I'm not too keen on the idea of the signal staying on for 30 seconds, what would happen if say you took a left, and then the signal was still on as you went past a junction you don't want to turn down?
The mercury idea sounds good. That or an optional off button for the signal!


Joined Mar 22, 2007
Oh, and as for option 1, I found this small switch:
RS Switch UK

I'm not sure where you're from, but if it's the UK, that site has alot of switches. The linked ones, although small and not waterproof could work if they had some decent waterproof bubble thing to go in! :p

This one looks cool, but not sure how big it is
Another RS Button

Thread Starter


Joined Mar 26, 2007
Hey again Dave.

An update.
I have the kill switch working fine w/ a 12v auto relay. wired constantly on press momentary switch to break circuit, engine dies. Great.

Signals are fine as momentary.

HI/LO Beam toggle.

Using the same relay, I can toggle between hi and lo but the relay does not stay on. It keeps switching back to lo beam. I wonder if it's because I am using a 9 volt battery w/ an led. Maybe it needs 12v to lock?

This is what most of the motorcycle related sites seem to use. Simple but I can't figure the hi/lo.

I am going now to try a 12v source.

Those switches by the way look like they might actually fit. I'd have to buy one to find out though.