Hi to you all,my mate and i have cleaned every joint/connection we can find,fitted new hall sensor,tested ignition switch and run continuity on all wires that was safe to do so.Fuel pump runs no problem Four pin plug in tank replaced with the one found in relay box ,engine starts easy idles,runs perfect,clutch cable route ok not fouling on any wires,Still out on a ride the damn thing cuts out as before, Question?? IF the fuel pump was faulty would it cut signal/power to the injectors instantly,resulting in this cut out problem,Answers ASAP due to HARRI KARRI  Pending

PS THE PUMP AND FILTER are original to the bike .

moriarti wrote:Hi to you all,my mate and i have cleaned every joint/connection we can find,fitted new hall sensor,tested ignition switch and run continuity on all wires that was safe to do so.Fuel pump runs no problem Four pin plug in tank replaced with the one found in relay box ,engine starts easy idles,runs perfect,clutch cable route ok not fouling on any wires,Still out on a ride the damn thing cuts out as before, Question?? IF the fuel pump was faulty would it cut signal/power to the injectors instantly,resulting in this cut out problem,Answers ASAP due to HARRI KARRI  Pending

PS THE PUMP AND FILTER are original to the bike .

Have you checked this?
http://www.kforum-tech.com/electrical/EFI/bike-wont-start-EN.htm

I remember helping somebody having the same type of trouble. In the end we found that the culprit was the ignition computer shutting off the signal from pin #6 to pin #4 of the Fuel Injection Computer.

Possible cause:  Tank connector for fuel pump power.

You can jump power directly to the fuel pump.  (The smaller diameter terminal on the fuel pump is 12V+.)

moriarti wrote:Fuel pump runs no problem

The pump might run but what's the volume of fuel at the rail?

It could be so many things.
First of all, you have to know if the problem is the result of fuel supply failure or ignition failure.
Testing is the only way you will accomplish something.
I believe that my document is pretty comprehensive and easy to follow.

When still in New Zealand with a K100 it would intermittently just cut out and then come back on again.  Often this was when pulling out to pass which was very embarrassing at times!

I tested and tested and tested some more, but, in the end I put small LED's into ignition and fuel injector circuits and had them back up in a cluster at the side of the speedo.  This meant when riding along and it failed that I could see what LED went out and be able to narrow things down.

For me it ended up being one of the two pole relays in that one pole remained conducting but the other was dropping out.

No idea what your issue may be, but, this approach may be of assistance to finding your intermittent fault.

This is the perfect approach to troubleshoot an intermittent problem.

Okay, one from left field here.
I tried binning the throttle position sensor - it runs fine without it, but you get the closed throttle backfire etc. etc.

Then I tried permanently jumping the wide-open-throttle contact (the 'other' switch inside the throttle position sensor) I did this just in case the absence of a TPS meant I was losing a critical half horsepower or so at full stick.

It ran fine like this too.

...except it didn't. What it would do was lose power suddenly when pulling out to overtake. At all other times it ran fine, but the combination of a big handful of throttle at low to medium revs resulted in, I guess, overfuelling, because the fuel map was adding too much fuel for the actual throttle opening. The engine would only recover if you closed the throttle and let it come back in by itself, then it was fine again.

Took a while to figure that one out - mystery power loss just when you need it most. I ended up fitting a microswitch to replicate to WOT signal.

Maybe check your TPS? You could eliminate it by simply going out for a spin with the TPS disconnected - it'll run fine.

EDIT: and you've got a very early 1984 ECU same as me - the fuel maps include that part-throttle doohickey stuck on the back of the throttle rail too, just thinking...

WOW you guys never cease to amaze me,I will start THE list as soon as poss, thankfully i can call on a few mates to help out,starting with the easy test chris suggested