Like the over-under toilet paper roll issue. The next time that one rears its head, click here, bone-up on the topic, swig some beer to wet your whistle, then weigh in well-armed.
Back to the kill switch.
Every bike has one. Unless you ride a vintage bike, in which case, maybe not.
I don't think there is a topic that breaks more randomly among riders. Other topics that spawn vigorous debates, like counter-steering versus steering-by-leaning, tend to separate along experience lines, with the pros on the counter-steering side of the debate and the others on, well, the other side.
Not so with kill switch debates. There are expert riders on both sides of this one.
I'll do my best to summarize the arguments on both sides of the issue.
Arguments in favour of ignoring the kill switch:
- Always leave it in the run position, it serves no real purpose except shutting off the motor in an emergency (dropped bike, accident, stuck throttle, etc.);
- It's not designed for more than occasional use, using it two or three times a day will cause it to fail, and strand you with a bike that won't start;
- If you get into the habit of shutting the motor off with the kill switch, you'll forget to turn off the ignition and when you return to your bike you'll have a dead battery;
- If the bike is fuel injected, the kill switch will not turn off the fuel pump, and it is not good to have fuel pressure in the injector(s) with the motor not running; and
- If you use the kill switch and leave the ignition on, the headlight will overheat and melt the lens or headset cover (Vespa specific argument).
- If you make a point of using the kill switch to turn off the motor, in the event of an emergency, you'll already have the muscle memory and will be able to shut the bike off instantly;
- Kill switches may fail like any other switch, but actual failures are more of an urban myth than a real problem. The turn indicator switch gets far more use, does that fail very often?
- The kill switch is just literally handy. You can turn off the bike without taking your hand off the handle bar. It maintains total control over the bike until the engine is off, it's just a safer way to manage the bike;
- If you don't get into the habit of using both the kill switch and the ignition, some devil will flick your kill switch off on a whim, and when you attempt to get going, you'll end up thinking something died and your bike won't start. The kill switch won't be front of mind;
- If you're ever on a rental bike or a loaner, you won't be familiar with the ignition switch location and the distraction of locating the ignition switch while the bike is running is just another safety issue. Kill switches on the other hand are always located within easy reach on the handle bar; and
- The US Motorcycle Safety Foundation course teaches new riders always to use the kill switch.
The compelling reason as far as I am concerned is that if you don't get used to using it you'll eventually forget that it exists and you won't be able to figure out why your bike won't start if by some fluke (or courtesy of a passer-by) the kill switch gets flipped. The secondary arguments that work for me are the safety-related ones.
I got used to doing this with my carbed Vespa LX150. I noticed (and more importantly Susan noticed) that when I came home and parked the new fuel-injected bike, there was sometimes a raw gasoline odor in the garage.
I still use the kill switch for the same reasons, but now I have reversed the shut-off sequence. I turn off the ignition and then turn the kill switch off. It seems to solve the problem. I checked, and at least for a fuel-injected Vespa GTS 300, when you turn on the ignition with the kill switch on (i.e. disabling the motor), the fuel pump does activate. I take that to mean that the fuel remains pressurized when the kill switch stops the engine.
If you care to explore samples of the debate,
- click here for one of the ModernVespa threads,
- click here for one of the ADVrider threads, and
- click here for an interesting debate on Reddit.
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