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Kill switches on bikes with electronic fuel injection

Discussion in 'Bling and Appearance' at netrider.net.au started by Spud Gun, Oct 5, 2006.

  1. When I collected my bike yesterday, the guy said that I should never use the kill switch to stop the bike. I should always use the key as the kill switch is also an electrical kill switch so flicking it would mess up the mapping for the bikes electronic fuel injection. Is that right? If its that serious then why have it exposed like a carbed bikes kill swicth? I find it hard to believe that flicking the switch will screw up the fuel injection completely. Can someone shed some light on this for me please?


     
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  2. I don't think that's true at all.

    I use the key out of habit, I don't have a kill switch in the car. There's 0 chance of forgetting about turining it of that way either.

    On the other hand, I have laid the bike down and I used it then because it's an easy target when your on the side.
     
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  3. He did say that it should only be used in emergencies, and being on your side would count as one of those I reckon. Can you tell a difference in power or performance after flicking the kill switch on your bike?
     
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  4. I use my kill switch every time I get on the bike. It's fine, don't stress.
     
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  5. Think of it like pulling the power cord out of a computer, because that's exactly what it happening when you hit the kill switch. Probably 99 times out of 100 it will re-start OK, but once in a while it does cause a problem that means re-installing all the maps etc.
    It's just a good habit to get used to to turn it off with the key. The Kill needs to be obvious and available precisely because it is there to be used in emergencies.
     
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  6. Is this on the Trumpy? Well I always thought that is what the kill switch was there for, otherwise why would it even be on the bike. I use it all the time and the bike still runs a treat, I guess just send the manufaturer an email if possible and aske them their thoughts.
     
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  7. Yeah, the Triumph has EFI and the kill switch. I think I will contact them and undertsand the impact of it, and what to look for if it happens and I lose the mappings. Its funny you should mention the power cord on the PC Titus, thats the comparison that the mechanic gave as well, and it seems like a brutal thing to do to the electronic system. It just means breaking an old habit and starting a new one.
     
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  8. What it's there for is for is ONLY to stop the motor in an emergency situation, and it's mandated to be there by law.
    Part of the problem with hitting the Kill, is that the computer doesn't have an opportunity to log the "live" information it is holding into its memory, so that when you re-start there is no record of the circumstances in which the engine stopped last time. This means any fault cannot be diagnosed, and if the engine management system reads the sudden end-of file as an error (doesn't happen very often, but it does happen), it will simply refuse to start up.
    All of this of course, refers only to computer controlled injection systems.
     
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  9. I wait to be corrected, but what a load of crock. It's sighted where it is for accessibility. Mine is is labelled 'Run' and 'Stop'.

    I reckon I've started my bike thousands of times...and never a problem.
     
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  10. load of crap if you ask me....
    why would bike manufacturers include a kill switch
    if it would bugger up the EFI?

    My bikes owners manual tells the me to use it
    so have all the EFI bikes I have ridden in the past
    5 years or more
    therefore
    I ALWAYS use the kill switch on my ZX12r
    and it causes no problems


    sheesh...the things people dream up :?
     
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  11. I've been using it to turn off the bike regularly, however before turning the ignition off I always set it back to on.

    Haven't read anything about this sorta thing in the manual or anything. Can't see why it would be any different to turning the ignition? Can someone explain the difference?
     
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  12. It's hard to comprehend why a manufacturer would engineer such a design into the EFI. You'd think that the kill switch would simply be in parallel with the switch contacts in the ignition switch that does the same thing - to de-energise the ignition system.

    Interesting thing on the Blackbird though. If I hit the kill switch on it, the EFI fault light illuminates. It goes out when I reset the switch. Handy for those who can't figure out why the engine won't crank over.

    However, on another Honda, the VTR1000, the kill switch only kills the ignition. You can still crank it over without any other indication, other than it won't start.
     
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  13. Mate, EFI is basically controlled by a small microcontroller, they do have a correct way to power down and this is cut short if the kill switch is used. It is not a whole lot of crap. The kill switch , whether marked Kill or Stop is there for emergency operation not for normal operation.
     
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  14. Totally correct, mate. But don't bother... they're not listening :roll:
     
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  15. lol! And you assume that the operation of the switch is in some way different to the operation of the key?!!!

    They are both switches! They both provide a signal or indication to the engine management system to either run or stop.

    You also assume that data is being written to the management system in a way that would corrupt it should it be powered down suddenly.
     
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  16. Wrong (or maybe your sytem works differently?).
    Look at it like any other microprocessor - there is a standard shut-down procedure that closes data files before turning off power. Or you can turn off the power with the data files active. I know which I think is safer.
     
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  17. Like any other microprocessor (and believe me, i know this), correct shutdown process is incredibly quick and just requires a signal (like a switch value changing) to end all transactions and processing.

    I think you're getting mixed up with the Windows OS with a HDD that has open files that were critical to the operation of the OS. The graceful closure of those files was required (and essential). Again, you assume that
    1.) There is data being written
    2.) That the operation of a stop switch is different to the key
    3.) That the processor requires a graceful shutdown

    I can only speak from my experience of 8yrs of EFI equipped bikes and my tekky job in IT.
     
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  18. Look I always use my kill switch, but I'm concidering a cinvert. :p :grin: But the thing I can't understand, is that is seems on the SP2 that the kill switch only cuts the ignition spark, cos the starter motor will still turn over but there is just no spark. So my thought is that it isn't cutting the mapping data short. Still if this is the case for all EFI's then I guess I can understand why to use the key.
     
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  19. On my BMW the power supply to the ignition electrikery is held up briefly by a capacitor in the PSU/Regulator circuit when the power is switched off. I can't see why any other bike should be different.

    Having said that, the kill switch is designed and mandated as an emergency shut-down device, and right or wrong I don't use mine to shut the bike down, but only because I don't see the point of using two switches when one will do.

    edit - The kill switch on my Beemer leaves the lights on, so it clearly isn't killing the power, just the ignition.
     
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  20. Microcontrollers have no fancy shutdown disk parking requirements. If they do write to flash/eeprom then their powersupply must be designed to hold up for long enough to finish writing, which is a few milliseconds. If the enineers made their system that crap that its so sensitive then they should be shot, and I wouldnt have much faith in the ECU not having other bugs like cutting out mid corner.

    With the kill switch off (key on obviously) does your dash/clock/odometer/oil etc still come on?
    If so its not cutting the power to the ECU anyway is it.
     
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