This must be a problem that is prevalent in cooler or damper climates. While I've heard about it I have never actually had first hand experience of it. The problem with Guzzi's long standing and byzantine starting circuit is though well documented! Certainly adding a direct feed to pin #3 is a good idea. As is removing the starter motor cover and giving the earth strap mounting point a jolly good clean and smear with contact/terminal protectant.
In the orignial case mentione here though the fact that the bike is a very early Breva 1100 raises a couple of questions.
Some of the very early gearboxes used on Grisos and Brevas had a couple of problems. One was the rattling of the face cam shouck absorber on the input shaft due to insufficient pre-loading and the second one was that on a few boxes the retaining screws for one of the bearings, (I think the front input shaft bearing from memory?) were ommited and this allowed the bearing and shaft to 'Walk' back into the box. "So what the @#!#$# has this got to do with a starting problem?" you may ask? well the thing is to rectify either of these faults requires the gearbox to be disassembled. One of the things that has to be done to achieve this is that the neutral switch has to be removed and it seems that the switch is VERY sensitive. Guzzi actually posted out a service bulletin on the Servicemotoguzzi page stating that if the switch had been removed that on re-installation it is VITAL that a new crush washer be used and that the switch should be torqued EXACTLY to the prescibed torque! Failure to do this could lead to? Give you one guess........
So? Do you know if your gearbox needed either of the above mentioned repairs? If so it may well be that the crush washer wasn't replaced or the switch was incorrectly torqued. Not suggesting this IS the problem but it does make sense doesn't it? As for Dave's bike? god alone knows what happened to that poor thing after it was butchered by Retardus Maximus in NI!
Pete
Pete, just relating my personal experiences on my 05 Breva...
I had the pin three issue last year, it appeared during our UK summer and showed on one day which was particulary hot, though never on a cold engine, only when it had been parked for a few short minutes on a hot engine. Maybe not climate, but as mentioned on the Guzzitech forum I believe that it's the route the wiring takes before power gets to the relay and suffers a small voltage drop. All my electrical contacts appear good, they're all dry and clean, especially the earth.
I have also had an issue with the neutral switch a few weeks ago. The symptoms were that even though the bike was in neutral the green light wasn't on, and having the side stand down it wouldn't start. A bit of up and down with the lever eventually brought it back on but as the motor was trying to bust into life the vibration would flick the neutral switch and it would cut out. A few goes at this and it would start and off I went. I replaced the switch the week the trouble started, but not the crush washer, I tightened it by feel, not to a specific torque, I must have got it just about right. It's been fine since, no more neutral light issues or starting problems.
Iain