Just had the breakfluid changed and the fork oil changed gave the bike a test spin all good. Went back to the mechanic to pay and returned to bike no start. We taped the starter motor nó change. Tried push starting but no joy. The bikes light and start up lighting is working and no dimming of lights when starter button pressed. Tried the starter kill switch flicking over and back when started pressed no change.mechanic will check the side stand switch tomorrow. Any idea?

Side stand interlock? Would have thought the attempted push starting would have eliminated that as a potential problem.

Side stand switch highly likely. Try start with bike on centre stand and side stand up. Get in under and take a good look, you can get at the contact. DAMHIK. But I knew about it when it happened. Its the number one cause of what you have got.
Push start wont work with faulty side stand switch either. If you have a running K1100 it cuts out if you flick the side stand down.
It also makes sense as he would not have been at any of the electrical locations that give problems.

Yep we tried having it on the center stand. No joy.

If you have the bike on the centre stand you can see the contact buried in the assembly, just move the side stand up and down as you look and see places that move. I had to bend a little tab and it cured it.

Not sure if the K1100 is different from the K100 electric circuits but:

• If problem is kill switch related: Ignition on -  there will be no indication on the instrument cluster (apart from the ABS relay light blinking), head light will work normally but on pressing start button, nothing will happen and head light will not dim.
  
• If bike is in gear (without clutch pulled in or with side stand down), instrument cluster will be normal when you turn on the ignition, but nothing will happen when you press the start button. If head light is on, it will not dim. This sounds more like your symptom, which points to a problem with the clutch switch (combined with not being in neutral) or the side stand switch. If the side stand switch is stuck (so doesn't clear the interlock when you put the side stand up) then that is a very likely cause of your problem. You should be able to disconnect it - just remember to put your side stand up before you ride off!
  

Also....you get no brake light on if side stand switch is down..........discovered that last weekend when I was wiring the trailer socket.......

92KK 84WW Olaf wrote:If you have the bike on the centre stand you can see the contact buried in the assembly, just move the side stand up and down as you look and see places that move. I had to bend a little tab and it cured it.

Another quick fix I use is to put a short piece of vacuum hose over the tab that depresses the side stand switch.

Is the neutral light working? Pull the clutch in. Been caught out with that before today

I put mine on centre stand last night and side stand down, exactly as you have when I turned on ignition. As you put side stand up you hear the fuel pump priming.

Yep but no priming, Will have a look at it today hope it's straight forward.

Yep side stand switch has happened once since my last panicked post.I would like to keep it as it is a good safety measure.is it possible dirt stops the switch traveling back to home position as it is so infrequent?

Thanks for all you help and sharing your knowledge.

That k1100 lateral stand safety is a pin in the ass. What I mean is that it is good to have a safety preventing from driving with the lateral stand out, but letting the engine warm up with the bike on its lateral stand whilst you close the garage door, put your gloves on etc. - it is also true in the opposite direction, coming back home! - is most convenient and wished.

I know that some k1100 owners have prefered comfort to safety and have by-passed that safety. I find it dangerous and I did not want to do it. But I wanted my bike with its engine turning whilst in neutral. It is very simple to do and I wonder why the designers did not think of it themselves...

All you need is:
- a relay opened when not excited (terminal 87 and not 87a)
- a relay holder, if you find one..., or a plug fitting on the relay, in which case you need a relay with an extension permitting to fix it, or just individual connectors fitting on the relay ends, in which case you also need a relay with a body designed to be fixed on something.
- a wire connector with a hole dia 6 (to catch a ground on the bike)
- 4 lengths of about 0.8 m of electrical wire (1.5 mm2 is more than enough) to be at ease. Might be wise to have a specific colour for the wire which will be used for ground.
- the equipment for achieving electrical wires welding
- a few rilsan bands such as used by electricians for nicely fixing the wires
- eventually a grommet (not sure about the translation... it is a rubber ring in which a wire is inserted when going through a metallic or aggressive surface).

The principle is to put the contact of a relay in parallel with the lateral stand contact. The relay is active when the gearbox is in neutral, thus letting the power reach the fuel pump relay in spite of the lateral stand safety contact being open. The relay opens when you make the gestures intended to start your ride. Only then the fuel pump relay is cut and the engine stops if the lateral stand is out.

This is based on the fact that the only way the start button can send power to the starter motor relay is if it receives power from either the neutral gear signal lamp or from the clutch safety switch (which permits to start the engine even with a gear engaged). Consequently, when the gearbox is in neutral there is 12V in the wire between the start button and the clutch contact output. That wire is easy to find: just follow le line from the clutch handle and you arrive to a 2 way plug, under the tank, on the bike LH side. There are 2 wires : one is Green/Black and the other is Black/Green, which is different! The one we need is the Black/Green, on the bike harness side. Remove some plastic around it, wind around the end of one of the 4 bits of wire you have prepared, weld and insulate with a tape. That is the wire which will go to the extra relay terminal 85.

Whilst under the tank, fix the connector with a 6mm hole on another bit of wire and connect it to the bike ground, via a screw already used for that purpose at the top of the bike frame. That ground wire will go to the relay terminal 86.

Similarly, follow the wire coming from the lateral stand. It arrives to a relatively large plug, under the seat, at the battery level. On the harness side the wires connected to that plug are Green/Red for one and Green/Yellow for the other. Like for the wire earlier connected to the clutch circuit, properly weld and insulate a wire to each of those. Those wires will go to the relay terminal 30 and 87, without preference for one or the other.

Time now to connect all that together. Bring the various extra wires inside the relay box under the seat. For the wires coming from the front of the bike, it is possible to pass through the rubber part at the top of the box. A little touch of hot welder in the rubber and that is it. As concerns the wires coming from the bike side, that is where the grommets could be used. The box material being plastic... an unprotected hole in it presents no electrical hazard. At the limit a drop of silicone for water imperviousness... I never did it and my installation is 10 years old.

For fixing the relay, you will find in the bottom of the relay box a place which seems designed for that. It is possible to fix the relay with a Parker screw similar to those used for fixing many fairing elements on the bike.

The first time you test you are surprised because you expect that the engine stops when you engage the first gear. In fact it is when you release the clutch that the engine stops. You very quicky get used to it

This is the basic diagram (a diode is missing, preventing the neutral lamp to light up when not in neutral, when the clutch handle is actuated):

I have never subscribed to the idea of letting the engine warm up.

Fire it up, use 'choke' if necessary and ride off. But go gently in the first part of your journey. Less engine wear.

My K1100 doesn't have the temperature gauge up to normal until after 6 miles.

92KK 84WW Olaf wrote:I have never subscribed to the idea of letting the engine warm up.

And neither do the volks at BMW. All of the rider manuals recommend starting the bike and riding off. For example, from page 42 of the US K1100 Rider Manual:

Do not warm up the engine at idling speed. Move off immediately after starting.

Having played with these bikes quite a bit, I've found that letting the engine warm up at idle tends to foul the spark plugs, especially on K75s.