Hello Becky and welcome…am sure somebody will be along soon with some advice…x
I’m not that familiar with the small blocks, a quick Google search shows a couple of suitable systems, neither are cheap, both are over £300
Silent Hektik from NBS of Stafford or Sachse from Gutsibits.
Secondhand Bosch units do come up for sale on eBay a lot cheaper. I recall the bike has 2 of the Bosch units, one for each cylinder. It is unlikely both have failed at the same time, so could your fault be elsewhere, like the supply to the system, the ignition switches can be a bit troublesome at times.
Where abouts are you? Is there anyone locally who could help you out?
Ok if you have money to spend.
From Guzzi bits: Fits Moto Guzzi V35 ALL, V50 ALL, V65 ALL, 750S, V7 Sport, S3, 850/1000 ALL Models useful Moto Guzzi model information Elektronik Sachse Electronic Ignition Kit Bosch Models ELA44003 £320.00 INC VAT £266.67 EX VAT this is the price you will pay if you are ordering from outside the EU
I have fitted this system to my V50. Not quite true that it true fit to the smaller blocks. Mechanically it fits perfect to the front of the alternator leaving the old system in place. Just pull the plugs on the control boxes and the lead from the pick ups. The system has selectable ignition curves which are not quite right for the V50 but I selected curve 5 which seemed the best. I wrote an article in Gambalunga regarding the fitting of this it will be in the next issue.
The next system is by Silent Hektik. Again it mounts on the front of the alternator and this model is approx £390 and is fully programmable.
Both of these systems will help towards removing the flat spot though having two of these bikes the amount of ‘lag’ is quite different between the two bikes. One bike would not pull in top through the bad rev range. Only by changing down could one get over this patch.
This problem was removed in the Mk3 as the ignition is points and the the engines has larger inlet valves, carbs and the compression maybe greater as well. I personally believe that it poor gas burning/swirl at certain revs in the Mk2. The ignition system is not totally to blame. Great care has to be taken to get the ignition timing spot on with the original system and is a pain to do as it will take several goes. Best checked with a strobe afte being reassembled. I would love to be able to alter the ignition while on the go to obtain best results.
If you suffering from no sparks on both cylinders.
Check the main plug from the alternator housing. Their are two one for charging and the other for ignition. Pull the plug and scrape the male pins of the plug. Push it in out a few times. Check the earth cable on the coils from memory they share a common earth. The ignition switch as a previous member pointed out can also cause problems. You really need a wiring diagram and if you feel adventurous a multimeter and some basic electrical theory.
I would try to stay with the standard Bosch system correctly timed first. Then if you still have got a badly affected bike take the next expensive step.
Intermittent wiring connection to the kill switch. Check the switch and bypass it if in doubt. Also check where the loom for this passes by the steering lock stops at the bottom yoke.