Since all the previous tests have not given any solutions, here are few thoughts.....
Your comments are welcome.

Fuel Injectors:
On the K bikes, each fuel injector has a resistance of 16 Ohms.
They are wired in parallel.
If the 4 fuel injector coils are OK, the total resistance between the yellow/green and green/red* wires should be 4 Ohms :
Total resistance = 1/(1/16 + 1/16 + 1/16 + 1/16)

*According to the electrical wiring, the green/red wire become black after the plug of the altitude corrector. This was optional on US models only. If you measure the resistance at the plug off the EFI computer, the color of the wires should be Yellow/Green and black

if 1 injector coil is bad the total resistance will be 5.33 Ohms ( 1/(1/16 + 1/16 + 1/16) )
if 2 injector coils are bad, the total resistance will be 8 Ohms ( 1/(1/16 + 1/16) )
if 3 injector coils are bad the total resistance will be 16 Ohms ( 1/(1/16) )

Now, what would happen if one fuel injector is seized???
Would the intensity (I) in the circuit raise to the point that the EFI computer port would shut down?
I don't think that the coil will pull more intensity as I believe that the inductance stays constant (what ever load it has to pull) and the only factor to change the intensity is the physical shape ( # of turns and size of the wire making the coil, and the voltage applied to it...) joules, watts RLC circuit and coils study is so old that I just remember the name
If you have the knowledge, please let me know if I am wrong

HALL Sensor:
Nobody had spoken about the HALL sensors.
If I remember correctly, if the Hall Effect Sensor is not giving a signal, the fuel pump gets shut down.
A good test would be to remove the fuel hose at fuel injector ramp and put it in a container. Then you pull the starter for 4-5 seconds to see if the flow of fuel is constant. (When people said I get flow from the pump, how long do they try it? ). Maybe Bosch has some sort of timer built in the EFI computer and if after a pre-programmed time it has not received a signal from the HALL, it will shut down the pump.
This would make sense as it would prevents flooding your cylinders if the engine is not turning.

Do you know what is the function of the spring under the valve cover?
- To provide a ground for the HALL sensor (You learn a lot on the internet)

Just an extra bit of information about troubleshooting the HALL sensor:
If your bike is cutting off or cannot rev at maximum speed when hot, it could be an internal crack in the HALL sensor. A microscopic crack on a board will expand when the device becomes hot and the contact will be open. When the device cools down, the crack closes and the system is running fine until it warms up again. (This is a common problem on computer motherboards)
I found on the IBMWR a way to test for such a problem.
Remove the cover of your HALL sensor, start the bike and with a hair dryer warm up the hall sensor. If the bike starts to run "crappy", shut off the heat of the air dryer and cool down the sensor. If the bike starts to run OK again, you found your problem.

For people have problem starting their bike, when you pull the starter, is your RPM going up on the tachometer? I believe that the RPM is feed by the back/blue wire on ignition coil #1 (Not sure if you should see it and is too cold to go on the shed and test it on the bike. People in a hot climate should be able to come with a quick answer)


For the few(many) people having troubles with their EFI, I would also check the wiring harness going to the EFI computer. Their is a very tight bend just before the plug and 1 wire maybe damaged. Simply cut the jacket around the wires and visually inspect each wires individually.

Fuel Injection pressure tester

By: Clarence Dold (from IBMWR)
Don mentions "special tools". The special tool that I used was an engine compression gauge. Mine was the really cheap kind. A dial with a stubby metal tube. The metal tube has a rubber sleeve on it. You jam the gauge against a spark plug hole and watch.

To use it to measure rotary engine compression (Oh, no, that's a $600 tool), I took the Schraeder valve out of the end of the tube, so it would release the reading, allowing the odd triple chamber rotary to show its true compression.

To use it to measure K-bike fuel pressure, I pulled the rubber thing off. This left me with a 3/8" metal pipe coming out of the gauge. I had a metal tee left over from something. I used the tee and a couple of chunks of "normal" fuel line to tee this gauge in, at the aft end of the fuel rail, where the hose feeds to the regulator.

Hitting the starter switch should cause the pressure to kick up to 60 psi. When the engine starts, vacuum control on the regulator will pull the pressure down to 40 psi. Turning the engine off should leave you with 40 psi. How long you wait for it to leak down wasn't mentioned. Mine was still at 40 psi 30 minutes after I shut the engine off.

If you disconnect the vacuum hose that controls the regulator (mine comes off the rear throttle body), the pressure would go up to 60 psi. Applying some vacuum to this line (I sucked on it) should drop it down. I can get the pressure down to about 30 psi. This portion of the test might be performed while the engine is running, or by "bumping" the starter switch, which lets the fuel pump run for a few seconds.

When my regulator was bad, it would stay at 60 psi. The vacuum line had no control at all. Even at 60 psi, the injectors didn't leak. I let it sit for several minutes. The "normal" fuel hoses that I was using would swell noticeably at the 60 psi range, so it would probably be wise to use some FI-rated hoses instead.

The compression gauge isn't expected to be accurate in this pressure range, but I was looking for go/no-go, not tuning help.

With the engine running and the pressure stuck at 60, the bike actually ran most of the time. It was hard to start, but if I could get it started, and keep the RPM up, it was usable. And this was on a K75, with no feedback in the FI system. A K12, with feedback, might well adjust the injection to accommodate the high fuel delivery, but the injectors might leak down when stopped, dumping some fuel into places you don't want it.


Bert

Hi Folks,
At least with Roy we know the Hall effect sensor is producing a signal as he has diagnosed he has sparks.
Regards,
K-BIKE

As mentioned we know with Roys and I think Bills that they are getting a spark and we know Mals is working but what happens if only half the Hall effect sensor is working causing the timing to be completely out of sorts.

To throw a real spanner in the works, what about a broken cam chain. I know you would expect some horrible noises unless it has just fallen into the bottom of the cover, but I know of modern cars with timing belts that fail they just stop and luckily no engine damage.

The fuel pressure thing keeps cropping up to but I am not sure how relevant it is to get the bike to at least cough. I had my tank disconnected for a week when I was fixing another problem and it still tried to fire as soon as I cranked it over with the tank nowhere in sight. Tried a second time as well with a smaller result.

Just throwing random thoughts now as I am completely out of ideas.

Regards,

Phil

Hi Folks,
Well I am not sure if Roy et al checked both cylinder banks to ensure spark on both but I would expect at least firing and plug wetting if fuel was getting through. Also the puffing from the exhaust that Roy noted shows the cams are turning.
Regards,
K-BIKE

yeah but if it a dohc and a free turning motor a coulde of the ex valves maybe left open all the time chuffing out gass when ever the piston goes up

I was reading a post on another forum with the suggestion of a broken cam chain and the response described the engine as being an "interference" type which to me indicates some fairly unpleasant noises if one was to break so I think I will scratch my cam chain idea or at least make it an even more remote possibility.

Regards,

Phil

Hi Folks,
If one injector was seized shut it would not pass fuel but the other 3 would and being seized shut would not cause the EFI to shut down as there would be no massive change in the inrush or steady state current to cause a shut down. If it was seized open then fuel would squirt as long as the fuel pump runs.
Regards,
K-BIKE

i have seen efi systems newer models it was a car as well a 300zx i think had 2 seized injectors out of 6, the car ran on the other 4 cyls like there was nothing wrong. apart from the 2 missing cyls.and with the cam chain break my father inlaw timing belt broke on his dawoo and bent nearly all the valves with out a sound at 100km\h.
i think if u dont have a compression tester pull all the plugs out and jam a rag in every hole (so its tight sealing) and hit the starter if 1 cly is lacking youl know by the pop and volicty the rag flyes out.

I was reading some fault finding on another forum (ibmw.org) relating to
an R1100RT. They were testing the fuel pump and HES and the method
suggested was to take the cover of the HES and turn the engine manually
with the ignition on (presumably plugs removed) and check that the fuel
pump cycles every time the HES is activated.

I presume the older K's don't pulse the fuel pump but it seems like a
reasonably easy way to check spark , HES, and injectors, as would they
not squirt with each rotation of the engine and because it is only
turning very slowly the risk of fire etc. should be reduced?

And if the injectors did not fire you might still get a pulse from the FI unit only much slower.

Regards,

Phil

The Hall Effect Sensor only has two triggers so is not able to fire spark plugs individually (unlike a distributor on a car) so it fires two spark plugs at a time e.g. 1 and 4 together then 2 and 3. Only one cylinder is on the compression stroke at one time so only one spark plug fires the mixture.

The other is described as a "wasted" spark.

Regards,

Phil

And for the same reason the bike injects twice, once against the closed intake valve and the other time when it is open. Just taking the injectors out with the rail attached should allow you to test them outside the bike to see if they work (taking all safety percautions!).