No Spark/Not Starting (1982 Maxim 650)

Thanks in advance, im gotten alot of great advice and my back is starting to come together.
I have in no spark in 3, and a weak tiny, yellow spark in one spark plug. The neutral light doesn't always come on, the starter button doesn't always work, and sometimes when i turn the key i get no power. So there must be some loose wire right? The 4 fuses under the seat are all good, wheres a good place to start looking for this problem, thanks!
DG

 

check connections with a meter, sometimes the fuse itself is good but its connection to the fuse panel is not. also may need to check and clean connectors, there are several on the harness under the tank and in the headlight. there is a main fuse that may not be part of your fuse panel, mine is in a separate inline connector, that would be a place to check if you are losing your main power (nothing lights up when you turn the key). keep an eye out for potential loose wires in the connectors, may need to cut and recrimp. i had that same problem with the main power connector the other day. could also be a weak connection in the ignition switch itself, i've had to take one apart once and polish the points with a dremel. but eliminate the obvious first: fuses/connectors.

 

my fuse was good but my connection was dirty. i'd be driving down the road and my turn signals and brake lights wouldn't work and my dash lights for the neutral, highbeam, oil, and turn. cleaned teh fuse connection. haven't had a problem yet.

 

thanks, im definitely going to clean the connections and check the fuse housings. I opened up the right side handlebar/start button. This part was loose, is this something that grounds the start button to the handlebar? I havent been able to figure out how it goes in yet

 

tried it this way, now i have spark in all 4 spark plugs. The lightbulbs in the speedometer still go on and off. In the headlight basket theres 4 bullet connectors with missing wires. I think this might be the reason the previous owner abandoned it! Next thing im going to clean all connections i can see thoroughly,