Fuse B or not to be

Puzzle me this 'grasshoppers'  ........... rode the GRiSO to work and parked it. 6 or 7 hours later, I confidently walk up to the bike to warm her up while I donned my riding gear ............. the ignition was not working, NOTHING. But i did have the dash and functions, blinkers, horn etc. The dash was telling me that the battery was a willing and healthy 12.1V  . Ralfz talked me through a checklist of usual and unusual possible causes (thanks Ralph  ). As it turned out, fuse B was blown. Once replaced with one of the spares, she fired up immediately and I rode home with not a hint of a problem. What would cause the fuse to blow while the bike was parked ??

It blew as soon as you hit the start button. If there is any sort of resistance increase in the system the fuse will tend to blow. It isn't helped by the fact that the poxy electrons have to run up and down the bike a dozen times before they get to the relay that shares a common feed for trigger and delivery. It has always been so with Guzzi, god knows why!

Anyway, check battery terminals and clean, check earth points and clean, (Main earths are on the top mount under the starter motor cover.), make sure the battery is good and if you're up for it put in a fused direct feed to the trigger side of the starter relay.

Pete

thanks Pete, that sounds pretty well what must have happened .......... as I later discovered, the number plate light was US (which is serviced by the very same fuse as the ignition relay) I removed the bulb which looked good and confirmed by a multimeter, checked the wiring and connector 2 pin plug under the seat and was all ok ........ put it all back together and the plate light was now working as was the ignition circuit. Perhaps a high resistance short in the number plate light or wiring which was remedied with some attention???

I had the same starting problem here last Sunday, but no time to gin around with 'B' fuses. Sooo.... jumped on the wife's ever reliable small block Sone and headed off to a mate's woodworking exhibition opening at the Channon Gallery. That night I replaced the fuse only to have it fail again...... mmm, not good.

But then searched here, found this thread, read Pete's advice and spent a few minutes working on the big girl this afternoon. Blew another fuse before getting to the two main earth cables located just where Pete said they would be. And even though they looked like new I cleaned the contacts up with a bit of wet and dry, then hit the tit and guess what - she fired up strongly....... success yaaaaay!

Would you please send some pictures of the earth points. Please help me understand.

Thank you very much.