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weird question...

how do you turn off your bike?

i always used the kill switch on all of my bikes but according to the manual (2006 F4 1000S) it is not recommended.
that was actually new to me and i never really thought about it until i read it.

is there a reason for it?
 

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I use the key. Originally, in my MSF course, I was told to use the kill switch and the Guzzi recommends the kill switch as well. I use the key on it, mainly because habit formed from the reactivation switch on the MV being kind of awkward to get to (on mine its kind of under the throttle cables.
 

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I use the kill switch when at a limited, temporary stop but if I'm getting off the bike then it's the key. Would be interested in know the core difference between the two approaches.
 

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It could be MV just being "safe".
As the kill switch may only disable the ignition/fuel/start circuit(?) and leave the other systems "hot".
Would need to look at the wiring diagrams.

I use the key 99%.

Ed:)
 

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The theory is..If you use the kill switch then you can get a reverse emf in the harness . Using the ignition switch breaks the circuits...

I looked all of this up a little while back and became a pocket expert but people in the pub started avoiding me lol



For the same reason there is a diode across the starter solenoid..


" The solenoid on the starter is electrically similar to an ignition coil, when the solenoid is de-energized, the collapsing magnetic field produces an EMF pulse that is conducted back to the ignition switch. My 35Mhz scope measured that pulse to be greater than 350V and is just enough to produce an arc across the starter switch contacts. After a few hundred or thousand events, the switch get grunged and makes poor contact which results in a lower than normal starter solenoid pull current. If it is hot or the solenoid is dry (or even very cold) the combination will result in a non-crankstart."

joe
 

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I use the key normally and use the kill switch/key when teaching my MSF courses. Have to set a good example, I guess..

As far as leaving the fans running, I heard that's a bad idea? If you leave the fans on to cool the radiators, the coolant will cool off, but when you start the bike again, you could have a bunch of low-temp coolant rush through the engine and possibly cause cracking. I don't know if anyone else has heard this? Not sure how true it is, but I don't let my fans run while the bike's off anymore.
 

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"If you leave the fans on to cool the radiators, the coolant will cool off"

The coolant doesn't get to that low a temp just sitting there with fans on, and the fans would only be cooling the stuff in the radiator and moving air around the outside of the engine. The only time a running fan would do any good once the engine was off is if a coolant circuit was circulated by an electric pump, as with many (not-American) turbocharger coolant circuits. The coolant pump keeps circulating the fluid until a preset temp is reached.

So... You aren't going to cold shock a hot engine by letting the fans run once the engine is off. All you are doing is draining the battery by letting fans run on and on.
 

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Yeah, that's what I figured. It's better to be safe than sorry, though. Also, I think ambient air temperature would have a lot to do with it. Different strokes! :)
 

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I only let the fans do the work when I am putting the bike in the garage.

Normally it is straight off via the key and leave the air to do it's work
 

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I use the key out of habit.
 

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The theory is..If you use the kill switch then you can get a reverse emf in the harness . Using the ignition switch breaks the circuits...

I looked all of this up a little while back and became a pocket expert but people in the pub started avoiding me lol



For the same reason there is a diode across the starter solenoid..


" The solenoid on the starter is electrically similar to an ignition coil, when the solenoid is de-energized, the collapsing magnetic field produces an EMF pulse that is conducted back to the ignition switch. My 35Mhz scope measured that pulse to be greater than 350V and is just enough to produce an arc across the starter switch contacts. After a few hundred or thousand events, the switch get grunged and makes poor contact which results in a lower than normal starter solenoid pull current. If it is hot or the solenoid is dry (or even very cold) the combination will result in a non-crankstart."

joe
Wow, you win the Internet.
 

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The theory is..If you use the kill switch then you can get a reverse emf in the harness . Using the ignition switch breaks the circuits...

I looked all of this up a little while back and became a pocket expert but people in the pub started avoiding me lol



For the same reason there is a diode across the starter solenoid..


" The solenoid on the starter is electrically similar to an ignition coil, when the solenoid is de-energized, the collapsing magnetic field produces an EMF pulse that is conducted back to the ignition switch. My 35Mhz scope measured that pulse to be greater than 350V and is just enough to produce an arc across the starter switch contacts. After a few hundred or thousand events, the switch get grunged and makes poor contact which results in a lower than normal starter solenoid pull current. If it is hot or the solenoid is dry (or even very cold) the combination will result in a non-crankstart."

joe
I don't get this, it's a coil getting energised, either it's in or it's not, it might chatter if something is wrong with the coil, but I'm not sure this is applicable Joe, sorry.

Interesting. Fans on my last bike would keep running for a while even with kill switch and removed keys.
You have a problem mate.

I use the key normally and use the kill switch/key when teaching my MSF courses. Have to set a good example, I guess..

As far as leaving the fans running, I heard that's a bad idea? If you leave the fans on to cool the radiators, the coolant will cool off, but when you start the bike again, you could have a bunch of low-temp coolant rush through the engine and possibly cause cracking. I don't know if anyone else has heard this? Not sure how true it is, but I don't let my fans run while the bike's off anymore.
That's a funny one Nick, not going to happen mate.

FWIW, any of you know what the ECU does every time you turn the ignition of as apposed to only turning the kill switch off ?
 

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That's a funny one Nick, not going to happen mate.

FWIW, any of you know what the ECU does every time you turn the ignition of as apposed to only turning the kill switch off ?
Hey now, don't shoot the messenger. :ahhh:


No idea! Educate us, oh enlightened one.
 

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Well it's amazing what you can read on the back of a beer mat boys..

Back EMF...That's why there is a diode in parallel with the primary side of the starter solenoid and that is why there is an ignition switch. The emergency "kill switch is there to stop the engine in an emergency.

Back EMF is a reversal in voltage . It;s physics fellas. I'm not making it up , Honest : )
 
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