After a frustrating couple of weeks trying to identify and source the startup maintainance and main injection relays (the ones with the back-emf suppression diode connected in series), the ones from the factory arrived. Great - now I have some proper part numbers to work with.
Meh. It appears that they are specialist enough to be not available on the open market. The part numbers are:
Startup Maintenance Relay - LI L5A 12V30A. There’s another six digits on there but they are the month and year of manufacture. There’s no obvious mfr name on them at all.
Main Injection Relay - V23134-B52-X506. TE Connectivity will sell you a minimum quantity of 5000 (
).
The good news is that they are common across just about all of the surviving Italian bike manufacturers. Ducati and Aprilia both use them extensively. I’ve found s/h ones scattered across ebay UK at between £12 and £15 each. Fowlers of Bristol will sell you both of them at £24.95 for the Startup Maintenance Relay and £40-odd (I lost the page and couldn’t find it again) for the Main Injection Relay - on the webpage they have a long list of Aprilias and Guzzis that they fit. Gutsibits don’t stock them; I’m not surprised because I’m pretty sure they’re not a ‘fast moving’ item.
I just hope this helps someone else.
Final word: don’t use any other relays than these because as Brian said in another thread, the ECU requires to see the diode as part of the system healthcheck.
(But I was so relieved when that damnable warning light finally went out! 
).
[Edit] Ugh - shoulda looked at Stein-Dinse first. They are by far the cheapest place to to buy at less than half the UK price. €11.00 for the Startup Maintenance Relay and €20.72 for the Main Injection Relay. Chuck in the postage and that’s still way cheaper than the UK.
