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From my notes, there are two coils in the Valeo solenoid (the old Bosch and the new Chinese starters all have 2 coils as well) One is 1.05 Ohms from the spade connector to chassis by Ohms law that will draw 12/1.05 = 11.4 Amps, this coil is powered up as long as the bike is cranking over. (I call this the Holding Coil, it can never close the solenoid just strong enough to hold it in place) The other coil is only 0.25 Ohms and goes from the spade connector to downstream of the main contact and across the armature. (I call this the Grunt Coil, it does most of the hard work if its wired right that is) The Grunt coil is turned off once the solenoid is engaged. The armature is so close to zero ohms you can ignore that so by Ohms law 12/0.25 = 48 Amps, add the 11.4 and you have 59.4 Amps, in reality you get about 40 Amps. On the later bikes you get Startus Interuptus, the wiring is not up to it so the Voltage drops and the relay just clicks. Solenoid Magnetic Strength: The two coils both have about 300 turns, the magnetic strength is Amps x Turns = 3,420 AT for the first coil, 14,400 AT for the second coil (4 x as strong if its wired right) BTW if you try to measure the currents you cannot do it with a multimeter, the heavy current only lasts for about 50 milliseconds, too quick for a digital multimeter, there are ways of doing it if anyones interested. I have helped dozens of owners with Startus Interuptus, some other models suffer worse e.g. the CARC models that the wire from the relay to the solenoid is really tiny, it would be ok if the current was only ~10 Amps but its a real choke point for 40 Amps, my 07 Griso operated 3 x as fast just by increasing the wire to a No 18. Of course on the later 8 Valve bikes the wiring is even worse, they choked the current through the switch again. I wrote a letter to Piaggio about the problem, they sent me an acknowledgement but I suspect they filed it in the trash.

Fuse No 5 on the earlier VII should be a 20 Amp, not a 15. These earlier bikes are better wired in some ways, Fuse 5 is direct from the battery and feeds the Start relay, you should never have a problem with it failing to crank (provided it hasn't blown the fuse). The later bikes late 2003/2004 have the start relay fed from a switched fuse so they suffer from "Startus Interuptus" like many other models, how do I know this, because my 2001 was wired direct. I couldn't understand what SI was about until one day I discovered there are two coils in the solenoid, the solenoid has an inrush current around 40 Amps (too much for a 15 Amp fuse). Trace the wiring to and from Fuse 5 It comes straight from the battery, goes to the Start relay through the normally closed contact to the headlight relay. Compare it to a later model. Here the start relay is fed from fuse 4 via the ignition switch, a 15 Amp fuse will probably never blow because it has half a mile of tiny wire to limit the current and the ability of the solenoid to engage the starter properly. You cannot simply feed the start relay direct or it will turn the headlight on, there's several ways around that.

thanks docc. I didn't know about that potential issue and will check it out.

Since both daviscr5 and Tom in Virginia have the later wiring, then the OP, LowRyter, likely has a different problem. Assuming the relays are high current OMRON G8HE, it could be that removing and replacing relays repeatedly has weakened the relay base connections. Again, Kiwi_Roy to the rescue:

I did this as a preventative measure some time ago. I installed a larger relay into the circuit going to the starter solenoid . This remove the load from the factory wiring harness , fuses or relays . The original wire to the starter solenoid activates the relay with the relay controlling the starter solenoid . Pin 85 to ground , pin 30 to 12v , pin 86 to factory solenoid wire and pin 87 to the starter solenoid . I have done this on my 03 and I have done this on Ford farm tractors with Lucas starters . Any time you can make a Lucas anything work better...........

Will do this over winter. Fairly easy to check. Thanks docc! Kiwi-Roy: "I have helped dozens of owners with Startus Interuptus, some other models suffer worse e.g. the CARC models that the wire from the relay to the solenoid is really tiny, it would be ok if the current was only ~10 Amps but its a real choke point for 40 Amps, my 07 Griso operated 3 x as fast just by increasing the wire to a No 18. Of course on the later 8 Valve bikes the wiring is even worse, they choked the current through the switch again." Thanks Roy, I will have to look at this condition on my 2016 Norge. It "cranks" with a good battery no problem but just doesn't seem to have much "umphh". Ahh, the life of owning Moto Guzzi's ... the work list is rapidly outnumbering the Honey-Do list!

That sounds right the headlight relay would close but I don't see how loose magnets would blow a fuse. A loose main battery connection could cause the fuse to blow, the heavy current coil is turned On until the contact closes feeding 12 Volts to the motor armature, I tested that by loosening the positive feed to the solenoid, the fuse blew in less than a second.

Nicely put, Kiwi_Roy! So (on the early wiring), blowing Fuse5 during a start attempt could be connections to the Starter Solenoid or faulty starter (like the common internal loose magnets)? If it blows turning the key on (Start Relay normally closed), the fault is in the Headlight Relay circuit?

I would suggest opening the headlamp bucket and inspecting the 3-way H4 bub connector for heat damage. I have also seen a damaged H4 bulb filament cause a short. Faulty Relay#2, or its connections underneath, is also worth checking.