Either suggestion - 1N4742 or 1N4743 - will work. Maximum surge current is about 370 mA, nominal current is about 75 mA. The 1N4007 has a forward current rating of 1A. All of this current is passed in the few milliseconds after the ground is switched off anyway.

Finally got back to this. I installed my new (to me) ICU and that solved the starting issue. I also went back to my OEM relay after cleaning up the contact with 400 grit sandpaper. I took a look at the inside of the Suzuki relay and it didn't appear to have a snubber circuit or any resistor in it. I couldn't open it all the way because the construction was such that it would have required cutting the wires that go to pins 86 and 87 (the 12v and to ground). Since I couldn't get it all the way open without destruction, I didn't do it. I actually also built my own snubber circuit per Robmacs advice, but was too chicken to use it. Since the old relay looked pretty good after rehab I just went with it instead.BTW my old relay appears to only have a resistor inside.

Since my ICU was damaged, I thought I'd open it to see if a fix as per Charlie's comment might be possible. Best I can tell the plug is soldered to the board in a way that would require cutting the plug from the board to get the board out. I gave up before manhandling it in that way. If anyone wants my old ICU to experiment with, its yours for price of postage. Otherwise I'll take it for recycling when I have a chance in a few days.

yeah, i wouldn't mind experimenting with it ...but scared of the shipping charges , as us has some pretty weird postal rates ...maybe more unpredictable might be a better expression .

but ...if it was possible ...and under $20 us ... hey ill take it Justin

could help out some poor soul in the future



glad you got it solved ....in around about kind of way ,,,good work for sticking with it ...many wouldn't !

cheers

Charlie, PM me your address and I'll check on postal rates. Might be close at $20. If within a few $ of that I'd even cover the difference as a public service since I'm sure you'll share what you learn with the forum.

Don't mean to rub it in but tooling around with the electrics got mine to start... bad connections I thinking - had the relays in and out and can't pin point the exact problem but had been through most things

pulled, cleaned and tested alternator and starter motor, relays and fuses, battery, earth, wiring, instrument panel (speedo still dead), plugs... and lo! ignition. 

Don't forget to walk away and communicate with the long suffering others in the household.

Anyway. hang in there. It will start. You are in the right place for advice. 

Guy

Guy, good advice always.  Amazing how much havoc a dirty or partially disconnected plug can cause.  I've been the victim of this twice now.  Hope that others have had the chance to learn from (or at least been entertained by) my (incessant) posts chasing down these issues.   

I am up and running now. In this case the problem was a bad ICU (probably damaged by the non OEM starter relay I tried).  But, of course, I put that relay in after I had the infamous sticking starter relay problem, which was caused by low battery, which was caused by much testing that caused the battery to run down, during which testing I also fried a set of Hall Effect Sensors.  All of this also gave me the chance to replace my coils (one of which was going bad anyway). And for good measure, I also replaced the spark plug leads/wires as well.  But, after all that, I finally diagnosed the original problem as a dirty connection that was causing a bizarre intermittent low power/misfiring issue that kicked off this whole chain of events.

Feeling a bit foolish on all of this.  However, I suppose that the upside to all of this is that I've learned a lot and most of my electrical system is now refreshed and in good shape. Live and learn, I guess!

I ended up replacing the plug with a 4 pin 6.4mm square plug on both the K100 and K1100 and no more trouble.  I also made the lead a bit longer to be able to lift the tank more.