What's the clutch doin? How are you trying to start it? Cable, lever, the arm mechanic that's on the right side under the foot floorboards and then inside that right side cover has a "spring" 2 actually, little pieces of what look like sheet metal but I guess it's some type of spring steel they're stacked on top of each other one is a little longer than the other and they have a bend in them and then there's also the clutch material itself and then the little ball in the center which minarelli s are notorious for having wear flat and then they dont engage.
Oh and also don't forget about the tail light thing. If the tail lights burned out the bike won't start I just took the bulb out and kind of hotwired my tail light take the red plastic cover off of the tail light and it's pretty simple but you'll see how the circuitry works It's little brass strips inside of there and also to do was take like a paper clip or a piece of tin foil or whatever and connect the one little zigzag strip to the next so I don't have a tail light anymore but the bike doesn't know that it thinks it works I just ended up spray painting my tail light cover black so you can't tell that it's burned out so the cops don't mess with me and it's been working fine ever since. Other than those things there from what you described I can't imagine what it might be It's got to be the timing or what I mentioned sadly I don't know s*** about the time and it's one of the few things on this bike I haven't messed with I've done points on my other bikes and stuff but never opened up that side of my minarelli