Kill switches, friend or foe?

[Scout63]

Whats the consensus on handlebar kill switches?  I never use them in regular riding since if I do I end up leaving the headlight on overnight.  Also, most roadside failures involve my not noticing that it is off. I just bypassed the switch on my Ducati 860. Am I crazy?

[Zenermaniac]

In close to 50 years of riding I have never utilized it.
One time a friend of mine at work tried to start his Yamaha to go to lunch but it wouldn’t turn over. We tried to push start it back and forth across the parking lot to no avail. After we were both worn out he saw the kill switch was activated. They are an evil contrivance, lol.

[guzzista]

Methinks friends. With a relay controlled dedicated circuit to coils (best way to have direct power to coils), using a series switch on the ground side of the relay ( kill switch) is a good thing (YMMV)

[AJ Huff]

I always use the kill switch to turn off the bike. Then turn the key. Never done it any other way. To start the bike I always pull up the side stand, turn on the key, turn the kill switch on, start the bike. It's a ritual habit. Never had a problem.

-AJ

[Texas Turnip]

I started riding before there was kill switches. Never found a need for one. Enjoy whatever pleases you.

Tex

[Mayor_of_BBQ]

I can't imagine not using it...  But I didnt start riding until the 90's

I have only had one bike that didn't have one and you started it with a key like a car. (my ambo).. if was very odd to me.

[Old Jock]

I have them on the few bikes I own but never had to use them

I did have a mate who had a Tiger cub whose carb stuck wide open, I was riding with him at the time, we were both spotty squids and I'm dammed old, yet I still remember it like yesterday.

Both of us were speeding along and I wondered WTF is he was doing.

He was trying to pull off the HT lead, burning his hand on the head, then trying again. The cub was running a ridiculous high compression piston and a ported head (as I recall he kept rebuilding it after a few hundred miles)

Its output was chicken feed but still sufficient in the middle of the city to make it a bum clenching event. The single leading shoe drum brake uselsess and the location of the ignition switch somewhere obscure.

He did eventually find the HT lead and came to halt with an ashen face.

Although its never happened to me, there have been reports on here of some big block owners installing lighter carb springs and then having the slide(s) hang up inside the carb.

I'd rather have one than not, just for that "blue moon" ocassion you might need it.

[bigbikerrick]

I use it from time to time. Its never a problem, just an added convenience , if needed. My european dirt bikes in the 70s had a hold to stop kill button on the handlebars. That was the only way to shut off the engine, other than dumping the clutch in gear.
Rick.

[OldMojo]

They're handy if you find yourself parking on an uphill slope and need to keep the brake applied before you kill the engine. The combined start/kill button on the 1400 is a beautiful thing - impossible to leave the kill button on!

[pressureangle]

Some ECUs are set up to boot down on the switch before power is cut. I don't know the details, but apparently makes a happier computer if you do use the kill switch.

[Guzzistajohn]

They're fun to turn off at rally's when no one is watching    Then wait............... .

[Mr Revhead]

Seems a strange thing to make a fuss about.

Used mine once when I missteped and lost balance into a slow lie down. Hit the kill switch as I went over so no chance of oil starvation.
If I let go to find the key it would have been a hard drop

[Huzo]

Seems a strange thing to make a fuss about.

Used mine once when I missteped and lost balance into a slow lie down. Hit the kill switch as I went over so no chance of oil starvation.
If I let go to find the key it would have been a hard drop

It’s not really a fuss, just a whymsical observation and a rather sound one.
Yes they are an unnecessary complication ALMOST all of the time.
It’s necessary for some functions involving Guzzidiag, to turn the engine off with the kill switch and not the key during the process.
Only worthwhile use I can imagine….
Just another thing to stuff up.

[Frenchfrog]

I'm guessing but it could well be a legal requirement  in most markets Huzo

[kballowe]

We're riding 2-up most of the time, and it's a bit more convenient to kill the engine with the flip of the thumb, while keeping both hands on the handlebars and two fingers on the front brake.  Also leave the bike in 1st gear, so holding the clutch and the front brake at the same time makes it a bit awkward to reach for the ignition switch.

 

And YES, I have (accidentally) left the ignition switch in the "on" position..... and more than once.  I'm a slow learner.

 

[Huzo]

We're riding 2-up most of the time, and it's a bit more convenient to kill the engine with the flip of the thumb, while keeping both hands on the handlebars and two fingers on the front brake.  Also leave the bike in 1st gear, so holding the clutch and the front brake at the same time makes it a bit awkward to reach for the ignition switch.

 

And YES, I have (accidentally) left the ignition switch in the "on" position..... and more than once.  I'm a slow learner.

 

Just an “out there” idea, but how about resting your right foot on the brake while you attempt the tricky task of turning the key…

[Huzo]

I'm guessing but it could well be a legal requirement  in most markets Huzo

In all likelihood FF.

[kballowe]

Just an “out there” idea, but how about resting your right foot on the brake while you attempt the tricky task of turning the key…

Another crazy idea - how about if you could train my passenger to hold still until all is settled ?      

[bnucci24]

Just an “out there” idea, but how about resting your right foot on the brake while you attempt the tricky task of turning the key…

I use the KSwitch when I need both feet to balance for some reason and need to shut down while holding the front brake. Its only used if I drop the bike or think I might if I don't hang on with both hands on a hill or uneven ground.
Could maybe just drop the kickstand I think that kills the motor but I don't like to set faults on purpose.

[Wayne Orwig]

I have always used mine. Never had an issue.

[centauro]

Whats the consensus on handlebar kill switches?  I never use them in regular riding since if I do I end up leaving the headlight on overnight.  Also, most roadside failures involve my not noticing that it is off. I just bypassed the switch on my Ducati 860. Am I crazy?

No, you are certainly not crazy. Kill switches were only mandated on bikes since 1975, if I remember correctly, and they were always meant as an "emergency" engine shutoff device, not for regular use after parking the bike. The reason was that, back then, on most bikes (including Japanese) the key switch was not readily accessible in an emergency. The problem is that, over time, due to corrosion and resulting increased resistance of the kill switch wires and connectors, the coils receive only part of the current. And this, of course may lead to hard starts and failures.

The solution is what guzzista describes above, which I have also done to my SP: feed the coils via a fused relay directly from the battery, and using the original feed wire from the kill switch as the trigger signal to that relay.
Incidentally, this same concept is used for the headlight circuits, which saves the original handlebar switches from the same fate that kill switches suffer from.

The other good reason for adding the relays is that, in the extremely unlikely case of the relays not triggering to ON, their power contacts can be easily bypassed, something much harder and fiddly to do with the original switches, which provide no guarantee of success, and likely fire and smoke from the wires.

[Scout63]

No, you are certainly not crazy. Kill switches were only mandated on bikes since 1975, if I remember correctly, and they were always meant as an "emergency" engine shutoff device, not for regular use after parking the bike. The reason was that, back then, on most bikes (including Japanese) the key switch was not readily accessible in an emergency. The problem is that, over time, due to corrosion and resulting increased resistance of the kill switch wires and connectors, the coils receive only part of the current. And this, of course may lead to hard starts and failures.

The solution is what guzzista describes above, which I have also done to my SP: feed the coils via a fused relay directly from the battery, and using the original feed wire from the kill switch as the trigger signal to that relay.
Incidentally, this same concept is used for the headlight circuits, which saves the original handlebar switches from the same fate that kill switches suffer from.

The other good reason for adding the relays is that, in the extremely unlikely case of the relays not triggering to ON, their power contacts can be easily bypassed, something much harder and fiddly to do with the original switches, which provide no guarantee of success, and likely fire and smoke from the wires.

Great info Centauri.  I posted mostly to stimulate a little light chatter, but am also interested in how people use them. The Duc switch, originally a complicated magneto type grounding affair, was an enigma to me.  The bike had been swapped to coils which I imagine just route power through the switch. In the interest of eliminating a potential gremlin I bypassed it. Plus I’m immune from Guzzistajohn’s shenanigans.

[Old Jock]

One more thing to add from a pratical standpoint.

On older bikes still running points, the positive feed to the coils runs through the kill switch first.

Should you want to troubleshoot an electrical issue without running the engine, the kill switch isolates the coils perventing them from overheating and possible damage.

I'm hoping Guzzitsajohn's comment was tongue-in-cheek or he's super careful to make sure nobody's watching.

Being seen doing that over here would probably result in the protaginist being unable to s**t for a month after the rally.

[Chuck in Indiana]

IIRC, they were first used on dirt bikes in the 60s. They were a good thing when it was laying on it's side screaming it's guts out. Then, for whatever reason, they gravitated to road bikes. I never use it on road bikes, much to my chagrin. A friend came over one time for me to have a look at his bike with GuzziDiag. I couldn't get it to connect. Thought, WTF?? for entirely too long then finally realized he'd killed it with the kill switch. 

[Stretch]

This....

They're fun to turn off at rally's when no one is watching    Then wait............... .

Also been done in the parking lot where I work. ( I will now invoke my constitutional right to remain silent as
enumerated in the Bill of Rights.......  )

                                                     -Stretch

[larrys]

Only time I use it is to turn it back on after I've accidently bumped it off...
Larry

[Cdn850T5NT]

Should you want to troubleshoot an electrical issue without running the engine, the kill switch isolates the coils perventing them from overheating and possible damage.

My Dad told me to never leave the ignition on, but for short periods of time. I've ever since observed that rule. Could someone please explain, specifically, why? What could become damaged and why.

Thanks to any/all who take the time to comment/advise...

[Alfetta]

evolution is evolution...
first bikes i had were devoid of a kill switch, but that was also in the days when the location of the key switch could be about anywhere (under the seat, under the tank, on top of the tank, down by the carbs or on the bars). so i can see the legislation being made for a quick universal location. (notice that kill switches are always by one of the grip mounts).  As time marches on and the "Nany State" mentality somehow became main-stream, there is a plethora of devices to kill your engine. so perhaps the kill switch is truly not that useful in todays world, (but as we all know, it's not easy to un-mandate).

[Chuck in Indiana]

My Dad told me to never leave the ignition on, but for short periods of time. I've ever since observed that rule. Could someone please explain, specifically, why? What could become damaged and why.

Thanks to any/all who take the time to comment/advise...

(1) It can fry an electronic ignition such as a Dyna.
(2) It can overheat coils, with failure coming down the road.
(3) Both the above. 

[Road Rocket]

 My street Brit Bikes I build have no key switch...just a toggle switch near the twist grip..But on the race bikes, next to the clutch lever.