Yes, thanks for the wiring diagrams Chris which, as you say, are much clearer than the old Haynes one I have been using.
And I can report some success! The indicators, hazards etc are now working. With all the advice I gained a much greater understanding of the wiring and units, and therefore a bit more confidence tracking things through and which bits to pull apart. Cleaning the contacts was obviously the easiest first approach. So, I took both relays out of the rubber mount and gave all the contacts a good clean. And guess what, all the flashers, bar the on side rear came back into life. The errant rear one was traced to a loose connection under the seat.
So, back to taking the rear brake reservior off to get access to the starter relay. And clean all the contacts. Worked on the flashers, so I am hopeful.
Did you try the couple of tests I suggested above? If you did, what did you discover?
I would suggest trying the wiring mod suggested above before removing the relay.
If you do need to remove the relay, you shouldn’t need to remove the master cylnder to get it. Undo the pin that holds the side panel in. You should be able to get a 10mm spanner in behind it.
Glad the diagrams were of help, they certainly help me! I decided to draw the first one when I got fed up with trying to trace wires in a Haynes manual diagram, it was like “which baloon is Peter holding” puzzle you used to get in comics. Do the kids still get comics?
Not my post but thank you to Don West @Don-Spada for the wiring suggestion, this cured my long standing frustration with my 1000 SP non-starting and saved me a few quid as I was about to try a new starter motor having proved the relay was good.
Is it just me or is the SP loom more complicated than it needs to be? 
Cheers
Dave
It is a solution I came up with many many years ago when I first bought my Spada back in 1989! Very simple and very effective, Just one short length of red wire and 2 spade connectors. Don’t forget to tape up the spare brown terminal that you removed as it is live when the ignition is on.
Thanks Don, much appreciated, unfortunately not a complete cure, rode it today, stopped and would not start hot; relay clicks but nothing else. Battery is a year old so I think the solenoid or starter motor are failing when hot?
Bumped started it no problem (on a hill!) and when I got home it was fine, stopped and started it repeatedly with no issues. Frustrating intermittent fault I’ve had on it for a couple of years.
I could replace the wire from relay to solenoid as you have, other possibility is starter button wiring - Jap switchgear fitted and soldered onto existing might be an issue that reduces power to solenoid when hot?
Any ideas @Don-Spada before I get a new starter/solenoid appreciated
Cheers
To test the starter (and a good get you started when out and about) is to touch a piece of wire from the battery +ve terminal to the small spade connector on top of the solenoid.
This bypasses all the bikes wiring. If it works using this method, then the problem is with the bikes wiring, if it still plays up, then the fault is with the starter motor or solenoid.
Thanks, yes I did those tests the other day and all was good, unfortunately need to do it when it next fails to start! I actually had a heavy wire with me but forgot what needed connecting and wasn’t hanging around to find out as I was in danger of overheating myself…
Cheers
Sometimes just shorting across the 2 large termianls on the back of the solenoid with a large open ended spanner is enough to turn the starter motor a bit and then it will turn over on the button.
All handy get you home fixes.
Definitely. A couple of years ago same thing, I bumped it on the flat at a petrol station watched by about 10 bemused Harley riders. Not something I’m keen to repeat
lots of good advice here, but don’t overlook the possibility of something as simple as a loose or grubby spade connector* - perhaps not so much ‘hot’ as an intermittent connection when ridden (o;
never hurts to follow the wires and learn about your own machine (after 50 years they’re all a bit different) - and clean the connectors, maybe squeeze them gently to tighten loose ones, give them a squirt of your favourite automotive perfume, and etc. you’ll need a mug of tea and a @Chris950s wiring map.