In Case of Get-Off, Pull Here.Posted: December 5, 2010
Miss Busa’s How-To:
Installing a Tether Kill Switch
2010 BMW S1000RR
RND: Research & Delirium
I’ve googled myself to death trying figure out what type of switch I needed for the S1000RR and how to hook it up. A tension headache, one 800mg Ibuprofen, and a nap later I was still pretty much clueless. What little information I could dig up was conflicting and not very useful. Heck with it, I can figure this thing out myself. The biggest pain was trying to ascertain whether the S1000RR utilized a “normally closed” or “normally open” switch for the engine kill. Blech. Apparently nobody knew. The one reference I found on a certain S1000RR forum turned out to be wrong. Not that I gave much credibility to the thread, since it sucked and was no help to the people who wanted to know and were wanting to install a tether kill on their Double-R. The more I googled the more confusing it became. I finally found a reference on Pingel’s website that paired the words “normally open” and “magneto ignition” and “normally closed” and “battery ignition”. Magneto? I didn’t really know what exactly that was, but I’ve heard the term before in reference to old junk. So “normally closed” is what I put my money on. Off to buy a switch. My bike was in the shop, so I couldn’t look at it and couldn’t recall the information needed from memory. I really liked the PMR setup. The kill switch housing replaced part of the brake master cylinder bracket and it came with optional switch options. An extra switch? Always good for likely future upgrades. But I couldn’t recall if the S1000RR had a Nissin setup or not, so I decided to err on the safe side and bought an MPS switch, which was only half of an inch wide and fit 7/8-inch bars. It later turned out that I didn’t have the ½ inch to spare to cram that sucker onto the bar. Damn. I should have gone with my initial instinct. Oh well. Anybody want to buy a brand new MPS switch? Hit me up. ☺
Pingel has decent looking switches up for grabs, however I definitely don’t have room for them on my clip-ons and the panel-mounted option just didn’t fit the bill for me. I wear one-piece leathers. I have nowhere really to clip the tether other than making a wristband which will also keep the lanyard out of my way. I stole the wrist strap idea from the Pingel site, so kudos to them. ☺) I didn’t want a setup that would reach across bike or body parts. The Pingel switches to me look more to be made for cruisers or Harleys, not that I would have had the room for the bar-mounted ones anyway. I really wanted something a little more subtle and sporty.
Those are the only three viable options that I came up with in my research. There are other choices out there, but I dismissed them for various — now forgotten — reasons. I’m sure some of them were due to looks, design, price, or workmanship. I’m picky when it comes to my bike. I get the best I can afford and I want the stuff to last. The Pingel switches probably would outlast my bike. 😉
Slapped On The Wrist!
Yes, I could have just bought Pingel’s ready-made one, but I wanted to save some money and it would be kind of cool to make my own. I had most of the stuff already lying around from various other projects. I went to Joann’s to get a parachute buckle. 1-inch wide red canvas strapping, black retro-reflective iron-on ribbon, a 1-inch metal D-ring, the purchased $2 buckle and a sewing machine did the trick. I opted for white thread to do a little “contrast stitching”, but I should have just used red because my sewing skill leaves room for improvement… lots of wide-open room.
My difficulty finding a tether kill switch and trying to figure out how to install it stems largely from a lack of sufficient knowledge of electrical circuits, switches, basic wiring, and how ignition systems work. I had to beef up on long-forgotten high school physics subjects and educate myself in the application of the fine art of soldering wire joints. Basic Electrical Wiring 101 with a little something thrown in about relays, switching and simple circuitry.
Armed with a multimeter, Torx screwdrivers in various sizes, a clipboard, pen and my BlackBerry I got up close and personal with the Pirate. I took the engine switch/mode selector control pod apart and had a peek inside to figure out which one of the wires is the one the tether kill switch gets spliced into. This should also confirm whether or not the S1000RR employs a “normally closed” or “normally open” circuit. I had read somewhere that a good way to distinguish one from the other is by the number of wires that come out of the engine stop switch: two wires means “normally closed” and three wires is a sign of a “normally open” switch. I took the thing apart. I was presented with five wires hanging out of a keyed plug and a small PCB sporting three push buttons. Five wires? Great. I should have known. Why was I even thinking this could be as easy as following the one coming out of the stop engine button to note its color for later reference? I looked at the circuit board closely. I could definitely make out the paths of the circuitry. The pins on the plug are numbered. I also saw tiny numbers printed on the PCB. That made things a lot easier. The keyed plug also helped with keeping the orientation of things aligned correctly. It was time to draw a wiring diagram. After having studied the thing for a while it dawned on me that there is a place left for an option. A very faint cutout line on the switch’s front housing, an indentation on the PCB for an additional button with all the necessary circuitry in place, and three open slots in the keyed harness plug. Noting that, the whole mess became a little less confusing. Four functions, namely: Mode, Engine Stop, Engine Run, and Engine Start; one common connection to them all; it adds up to five wires. This started to actually make sense.
The multimeter proved useless, since the probes are too thick to fit into the harness plug and the entire circuit board is encased in some sort of clear plastic — to weatherproof the whole affair, I’m sure. So I ran my findings by Mr. Slow, but he refused to get involved, claiming lack of knowledge on the subject. I mulled it over in my head off and on for a few hours and then ended up sleeping on it.
I need a method to test my findings nondestructively. I don’t want to cut into a $1500 wiring harness on a hunch. I need some way to connect the male end with the female plug in isolation to engage in a little simulated wire snipping. Test leads. I could make myself little test leads to jump the pins. The female end is easy, but the pins on the male side need insulation to keep them electrically isolated from each other. After scrounging around for supplies I come up empty, naturally. I had, not too long ago, relocated my “computer graveyard” from its home in a closet to the neighborhood dumpster. It never fails. Hang on to the shite for years, not finding use for a single thing and as soon as you throw the crap out to make room for new junk you end up needing something from the pile.
I didn’t know what those “test leads” were actually called, so googling the subject proved to be coma-inducing, but eventually I hit on the name of the thing and once you can name it, you can find it in 0.0289 seconds. They are called jumper wires. They are used in robotics and prototyping to easily and quickly connect header pins on breadboard setups. They’re cheaper to buy than to make unless you have the stuff already lying around. I still would just buy them… trying to get those little fragile crimp pins onto the stripped end of a teeny wire sucks! I scored a pack of 10 6” male-to-female ones for about $4.
A Kick in the CANBus
With five jumpers in five different colors I set out to validate my thoughts on the kill switch subject. I dismantle the control pod once more, this time it only takes me a few minutes. I pull the plug out of its socket and use my spiffy wiring diagram to jumper the pins. After double-checking my work, I turn the ignition on and the RR begins its initialization. The RPM needle executes its customary sweep through the entire range of the dial, all LCD segments are displayed at once and all LED lights come on and blink off. The DTC and ABS indicators remain lit and blinking, as is expected. After the POST is complete, I put the transmission into Neutral and push the Engine Start button, the bike comes to life. No faults are tripped. All is as it should be. I pull the black wire that connects Pin 4. The engine dies instantly, just like it would if you had put the kickstand down while in gear. Still, no faults are thrown. I turn the ignition off and back on and try to start the bike again. Nothing. That too, is as it should be. I reinsert the wire to Pin 4, start the bike and press the Mode Selector button repeatedly to scroll through the four DTC modes. Again, all functions as expected.
Just for giggles, I yank Pin 5’s jumper wire out and nothing happens, the Pirate keeps on idling sedately. Pin 5 is the other half of the engine stop switch circuitry. Pin 4 is the connection that is common to all of the functions. Pin 5 is the wire I would have cut with a shaky, clammy hand had I have been on the bomb squad, sweating bullets with three seconds left on the ticker. Aren’t you glad I’m not on the bomb squad? I am. I am also glad that I took my time with this one and did it right. On the Hayabusa I would have spliced a wrongly cut wire back together. On the Beemer, the fear of the almighty CANBus and its renowned bitchiness saved me from myself.
The Pirate Is A Dead
This is a walkthrough of installing the PMR Stealth Kill Switch Combo. If you have another bar-mounted switch the install should be fairly similar.
- Remove the two-part housing of the right-side control pod. There is a small Torx-7 screw on the bottom part of the control pod’s housing, use firm, steady pressure and a precision screwdriver to remove it. Pull the front of the housing down and towards the front of the bike, until the plastic hinge on top separates and the two halves are free of each other.
- Unplug the harness plug from the top portion of the housing and place it out of the way.
- Use a Torx-27 socket or screwdriver to remove the two bracket bolts that secure the front brake lever assembly. Hold the assembly with one hand while you switch out the OEM bracket with the PMR switch housing and use the supplied #5 Allen bolts to fasten it to the bar. Don’t torque the bolts down just yet you still need to be able to move the assembly around a little.
- Route the wires of the tether kill switch to your liking and determine where you are going to splice them into the OEM harness.
- Once the position of your splice has been determined, cut the rubber tubing that protects the wires from the elements and from chafing. I used hubby’s nail scissors from his grooming kit, which are extremely pointy and razor sharp (shhhhhh! Don’t tell Mr. Slow.) Be careful not to nick the wires’ insulation. Once separated, cut a horizontal slit into the sleeve. This makes it easier to pull it out of the way and will also accommodate the added thickness of the bundle due to the newly spliced-in wires.
- Pull, then push-roll the tubing out of the way to expose the wires where you will splice in your tether kill. Give yourself plenty of space to work here.
- Snip the black wire with the blue stripe. That’s the common. IMPORTANT: If the colors of your harness wires do not match mine, you’ll have to find the wire that is connected to Pin 4.
- Strip about ½” of insulation off the ends of the four wires.
- Slip heat shrink tubing over the wires before you twist them together. I used 3/32” diameter tubing for the v-joint and 1/8” diameter for the straight joint. This way you won’t have to bend any wires and they’ll lie nice and flat against the harness bundle. It doesn’t matter which of the wires get paired, as long as you make the circuit whole again.
- Twist the wires together then solder the connections.
- Position the heat shrink over your solder joints and use a heat gun to shrink them down. Be careful where you point that thing, you don’t want to melt any of the S1000RR’s tasty bits, such as your brake or throttle lines.
[Alternatively, you can use crimp-style butt connectors, solder or crimp in quick disconnects, or use gel-filled 2-wire IDC (Insulation Displacement Connectors) butt splices but they will make your harness bulky and unless you can hide them somewhere, extremely visible.]
- To test your work crank up your bike. If it doesn’t start recheck your connections. Pull the plug out of the tether kill switch and your bike should die. If it doesn’t, in my best guesstimation I can’t help but assume that you screwed up somewhere… big time. I’m washing my hands of that one right now. *nods then turns and walks off quickly* “Gotta go!”
- Carefully pull the protective sleeving back into place. You might have to slit it some more to accommodate the new wires without bunching.
- Use electrical tape to wrap the spliced area tightly. It’s best to do it at a 45-degree angle and keep the stuff taught as you wrap the bundle.
- Follow up with friction tape to keep the electrical tape in place and from gumming up the works first time it gets hot and dusty. I also secured the ends with smallish cable ties to prevent them from unraveling.
- Go for a test ride. Don’t skip this step, it is VERY important to the entire process. It bears repeating: Go for a damn ride!
My work here is done.