Leave kill switch on?
pg 165
*Harley-Davidson cautions you against the use of non-standart parts such as aftermarket and custom made extended front forks which may adversely affect performance and handling. The use of any non-standard parts including mufflers may void your warranty according to terms of the warranty. Removing or altering factory installed standard parts may adversely affect performance which could result in death or serious injury.
I think that covers it regarding after-market parts. (mostly for warranty purposes).
Road Captain
Joined: Jul 2014
Posts: 721
Likes: 18
From: Galesville, WI
What is this 'kill switch' you guys speak of?
Oh wait a minute -- You mean the "I'm picking up my bike from service and I'm wondering why my bike won't start" switch? Or the "I'm riding under a tunnel and I'm going to make the bike backfire to shoot flames out of my pipes" switch?
Granted -- I don't think the "flame backfire" thing works with the EFI's, but they'll still pop nicely. On my old blue RK, it shot flames out nicely.**
Anyway -- I never use it. Heck, on my old metrics (Yama-Hondas), even the service guys would tell me never to use it. "Remember it's there in case you need it, but don't use it" is what they usually said.
** For the uninitiated, if you're "at speed" and there's at least some drag on the motor, if you flip that switch off/on once quickly, there's a very good chance you'll get a nice "POP" from it -- If carbed, a potential "flame pop" which is fun for the guys behind you. The pop itself is great if you spot wildlife up ahead and usually sends them running for cover.
Oh wait a minute -- You mean the "I'm picking up my bike from service and I'm wondering why my bike won't start" switch? Or the "I'm riding under a tunnel and I'm going to make the bike backfire to shoot flames out of my pipes" switch?
Granted -- I don't think the "flame backfire" thing works with the EFI's, but they'll still pop nicely. On my old blue RK, it shot flames out nicely.**
Anyway -- I never use it. Heck, on my old metrics (Yama-Hondas), even the service guys would tell me never to use it. "Remember it's there in case you need it, but don't use it" is what they usually said.
** For the uninitiated, if you're "at speed" and there's at least some drag on the motor, if you flip that switch off/on once quickly, there's a very good chance you'll get a nice "POP" from it -- If carbed, a potential "flame pop" which is fun for the guys behind you. The pop itself is great if you spot wildlife up ahead and usually sends them running for cover.
Road Warrior
Joined: Mar 2014
Posts: 1,973
Likes: 158
From: East Coast
Back in the day it was a kill button. A momentary button like a horn, 68 sportster, no battery to drain, kick start, choke, magneto, advance and retard the spark. shut her down with the kill button.
So I use the kill switch and then the ignition. Got to be your routine, not sure about any issues just using the ignition switch, but I don't think there would be any.
Maybe the manual discusses its use.
So I use the kill switch and then the ignition. Got to be your routine, not sure about any issues just using the ignition switch, but I don't think there would be any.
Maybe the manual discusses its use.
Road Warrior
Joined: Jul 2009
Posts: 1,979
Likes: 2
From: Northern Colorado
I have the factory security system with Smart Siren II alarm. If I use the ignition switch to shut off the motor I have exactly 4 seconds to plant the bike and dismount before it is activated. I don't like to be rushed, I use the kill switch! Then when I shut the rest of the bike off with the ignition switch I turn it straight to fork lock.
Last edited by NoCoLoco; Dec 19, 2014 at 01:12 PM.
Stellar HDF Member
Joined: Oct 2007
Posts: 2,806
Likes: 1,754
From: New Bern NC
What year is the manual you are looking it? When I wrenched at a dealer years ago we were having this discussion with our regional dealer rep (08 or 09) and he was saying that they were trying to get the manuals shut down procedure changed. Not sure if they ever did or not.
The main thing to know if you are using your run/kill switch to shut off your bike is to let the bike come to a complete idle before killing it. There was a service bulletin back in '08 for high idle problem, they bulletin had us cycle the ignition on and off several times to get the idle to re-set. What was happening is people were killing their bikes with the run switch and not letting the idle settle down, if the 2 sensors I was referring to in my earlier post (TPS and TGS) don't equal 5 VDC between them they they will reset to what it was last know. In other words if you soft kill your bike (run/kill switch) and the bike is not at a normal idle the 2 sensors might be adjusting and not be at 5 VDC, it can result in an ab-normal idle and need to be re-set. Worse case scenario it can put your bike into limp mode.
The main thing to know if you are using your run/kill switch to shut off your bike is to let the bike come to a complete idle before killing it. There was a service bulletin back in '08 for high idle problem, they bulletin had us cycle the ignition on and off several times to get the idle to re-set. What was happening is people were killing their bikes with the run switch and not letting the idle settle down, if the 2 sensors I was referring to in my earlier post (TPS and TGS) don't equal 5 VDC between them they they will reset to what it was last know. In other words if you soft kill your bike (run/kill switch) and the bike is not at a normal idle the 2 sensors might be adjusting and not be at 5 VDC, it can result in an ab-normal idle and need to be re-set. Worse case scenario it can put your bike into limp mode.
By the way welcome to Fredericksbug, I'm going to come down and check out your shop one day soon.
Seasoned HDF Member
Joined: Aug 2011
Posts: 11,814
Likes: 5,120
From: SW Ohio
The engine "Run" "Off" (or kill switch) only does half the job. Why get in the habit of doing just half a job? The MSF teaches it to new riders because it's in the same place on all motorcycles. No matter what bike they ride after that, they know how to shut the engine off; all while never having to take a hand off the bars. As with any training designed to meet the needs of the least proficient; it leaves something to be desired.
My guess is the MSF gets a kickback from battery manufacturers
My guess is the MSF gets a kickback from battery manufacturers
Actually unless one of the sensors is damaged they will ALWAYS read a 2.5v average regardless of the throttle position. Think of it this way at full throttle sensor one reads it's maximum and sensor two reads its minimum on a 1 to 5 volt scale. At idle they are reversed. it's a redundant safetyfeature, two sensors with three monitored outputs. All have to agree or the ECM envokes the dreaded limp home mode. The idle issue you are referring to is a glitch in the ECM taking a throttle reading at engine shut down when the engine isn't at idle.
By the way welcome to Fredericksbug, I'm going to come down and check out your shop one day soon.
By the way welcome to Fredericksbug, I'm going to come down and check out your shop one day soon.
The way it was explained to me is that the voltages are constantly changing and when you use the kill switch it doesn't shut everything off simultaneously like using the ignition switch, so if the TGS loses power a microsecond before the TPS sensor it can throw it out of whack, or vice versa. I just know that we don't have idle issues in customers bikes that only use the ignition switch.
Why do they only use a master ignition switch in cars?
Thanks for the welcome, my wife and I are really enjoying the area, hope to see you soon. It's always great meeting people from the forums.
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Extreme HDF Member
Joined: Nov 2007
Posts: 14,670
Likes: 139
From: East of the Sun, West of the Moon
Well, I've done it again, cut off the King via the kill switch on the bar and forgotten to turn off the tank-mounted switch, leaving the lights on & killing my battery! 
When I bought this in '09 the salesperson told me that I shouldn't leave the bar-mounted kill switch on b/c it would drain the battery, and I needed to use them both.
When I bought this in '09 the salesperson told me that I shouldn't leave the bar-mounted kill switch on b/c it would drain the battery, and I needed to use them both.I mostly remember to use both switches, but on average I forget and have drained battery issues at least twice or three times a year.
Can I just leave the kill switch on and only mess with the tank-mounted, or will that really give me trouble with draining the battery??
Can I just leave the kill switch on and only mess with the tank-mounted, or will that really give me trouble with draining the battery??
If you're going to use that run/stop switch. Make sure when you pull up and stop and are ready to turn it off, your hand is 100% OFF the throttle.