1988 Paso 750
I've got the Paso wiring diagram and my 88 is a little different from what's on there. I'v got a second red wire coming from the battery and it disappears into the loom. There's a 40 amp fuse in line? I've traced it to the wires coming out of the #2 part shown below. A couple of questions;

1) What is #1 & #2 in the pic? I assume one is rev counter and the other coil triggers?
2) Anybody else have that second wire off the battery with a fuse in it?

#1 is the pick up for the ignition timing and #2 is the alternator output .The in line fuse and extra red wire probly go to relays ( mounted elsewhere ) for the headlight and/or the ignition coils/ magic box..... which would be a good thing , or it could be the battery feed from the regulator . 40 amp is a big (ish) fuse
The rev counter is mechanical . The drive cable for it comes off the front cylinder head

I guess the differences of yours to the P750 in the wiring diagram is because you have a Marelli Digiplex ignition. There are a few guys who have that, too but I`ve never seen a wiring diagram for that version.

Is that a fuel line running close to the rear cylinder and under the header tube ?

G.

Not a fuel line, it's one of the breather lines. The bike is a late 88 with Digiplex and the gold colored valve covers and California (U.S) smog stuff. Thats the breather line from the carbon canister to the fuel tank.

Update - So I confirmed that the line with the 40 amp fuse is the feed from the alternator via the regulator. I assume then that feed is what charges the battery? If so, why would there be a fuse on that line at all? On older Paso's is there no fuse in that circuit? That's what the wiring diagram indicates. The wire does get pretty hot from the alternator back. There's a junction for the three wires at the front behind the steering tube. I pulled the rubber cover back and measured the temp at about 104 degrees after the bike had been running for awhile. It was the same temp at the junctions at the fuse. My fuse holder is toast (it had melted) so I'm going to replace it with something much more stout.