I have a strange problem on my K100LT. I bought the bike cheap with a holed crankcase, and replaced the engine with a 1984 motor which is the only one I could get at the time. The engine would not start,so i pulled the fuel rail and injectors out and rested them on the head to check that they were spraying. I was very surprised when the engine started and ran about 4000rpm, I replaced the rail and it slowed to idle and ran OK.
After riding 300miles from Alicante to Malaga Spain where I now live, the bike was parked up for six months without use, although I started it every couple of weeks. The other day I came to start the bike and it wouldn't have it. I removed the rail as before and the engine started and as before ran at 4500rpm, the amount of fuel being sprayed was a lot too much for the throttle position which was at idle. Now as soon as I replace the injectors in the head it dies. I have checked the MAF vane is free, the TPS does the normal click as the throttle is just opened. I have checked all the electrical leads and connectors, they look ok. I have been told that it could be the pressure regulator that is faulty,but that just lowers the pressure of 60psi from the pump to about 32psi to the injectors. could it be the FI computer? I just don't know. Any ideas would be welcome.

If your engine starts without the injectors ramp installed, this is because the cylinders have already enough fuel to burn.
I got a similar problem this spring, and the result of the investigation was a bad connection of the fuel Injection computer.
The bad thing is that the fuel leaked into the oil in the crankcase.
If you are finding your problem, before taking a long ride, check your oil level to be sure that your oil is not soiled.

Bert

Hi Thanks for that Bert, I have checked the FI connection, but I will go over it again and probably fit another FI computer just to see if it is faulty. I intend to do an oil and filter change when it is sorted
Cheers Ken

I have to add that why are the injectors putting out so much fuel as to make the engine run at 4000 rpm, when the throttle is closed, and when they are pushed into the head, the engine dies

This is a tough question!

I will only reply with assumptions...

If you try to start your engine with the injectors on and they are flooding the engine, when you remove the injector and try again, the excess of air entering the chamber by the injector holes will create a right mixture to explode and fire your engine.

You may have a problem with the air filter or the MAF (Mass Airflow Meter).
You would be surprised to see what you could find in the air filter canister if the bike was outside. Rodents like squirrels, mice,.. like to nest in it or use it as a safe storage for their food. I got this problem before and since then, I installed a screen at the mouth of the air filter intake. One winter, I removed 2 cups of sunflower seeds that a squirrel was dropping in my K75 filter. I had the same problem with my wife's car. The sunflower seeds were sprouting and growing on the air filter. She barely uses her car (15k in 6 years).
Rodents are also known to nest in mufflers. You will kill them when starting the engine, but it will stink for weeks after.
This seems to be funny, but it's the reality.

Hi again the saga continues, I have checked and cleaned all the plugs and sockets under the tank, some of them did have a blue deposit on them (corrosion) I have changed the TPS and the pressure regulator, checked that the MAF vane is free to swing. I have not looked at the temp sensor or the Halls sensors and FI computer. where can I find the correct readings I should be getting with a multimeter? The injectors are pulsing fuel ok, but are putting out sufficient to run at full throttle, and soaking the plugs. This is with the throttle at idle.

After you log in go to the "Portal' and you will find a very comprehensive FI/Ignition fault finding guide that will provide you with all the values you need.

When you push the injectors into the head with the engine running what happens if the throttle is open about half way or more?

Regards,

Phil

Check the connection to the coolent temperature sensor (located bottom right of the radiator as you look at the bike), if the resistances is too high it might be thinking it's -20 out there and enriching far too much.

Thanks I've found the fault guide. the engine dies whatever position the throttle is in. It's howling it down here at the moment, but when it dries up a bit I will check the water temp sensor.
Thanks