I am rebuilding a Yamaha at1, and for right now, I am trying to get a spark. I am looking at the schematic for the electrical system, and I have tried to simplify it, just for now to try and get a spark. I currently have my ignition coil wired directly to the battery, there's a yellow and a black wire hanging off the ignition coil, I have the yellow lead going to the +12v terminal battery, and the black wire is going to the ignition coil circuit screw terminal (marked with an orange label on the generator), which should lead to the contact switch and capacitor in parallel with each other, which leads into ground.
Is this enough to generate a spark? I currently don't have anything connected to the ground terminal on my battery, do I need to ground one of the points on generator? From looking at the schematic it wasn't totally clear.
Any help would be greatly appreciated! Thank you all very much

Sounds like an aftermarket coil? With those colors but "I think" 12 into one side & other down to the points & there should be spark at the plug. But firstly see if is there life at the points if you flick them. Even if you scratch a screwdriver around the points you should get life if you slightly separate the points. Or thinking again if you turned the motor to get points open then ran the screwdriver across the edge of points it'll spark at the plug randomly in line with how ya scratching. If that works but not by kicking over then clean the points so they'll contact. Not sure if the coil wires are a definite positive for the 'in' wire but I guess there is but think you'd get life either way even if it's not right. Getting out of my depth now. Could try black to the battery 12. Try an ohms meter between coil black & yellow to get a low ohms reading then on the K scale go from either of those small wires to the plug lead for a high reading statically. My At1 is magneto ignition so different horse entirely.

You are not going to get a spark with your ignition coil wired to the battery.

You need something to switch the current on and switch it off again at the same number of times the engine spins. I would say you have probably overheated your coil wiring it thus...

Battery to points on insulated side,  black wire to coil.

Tinkicker he has 12 to the coil & other wire to the points which is normal for a battery ignition two wire plug coil?? correct me!!. Cheers. ps, battery sure doesn't go to the points--has to go to coil first & other side down to the points.

Ah.  Yes, my bad.  AT1 has 12v system and electric start...

 

I'm guessing its this coil you have with a yellow & black, so 12volts will go to the yellow because the live wire from the loom for that will be a covered female connector so as not to short out by accidentally touching the frame etc. Meaning male yellow of the coil is the power in.

photos.app.goo.gl/UUZmimeNx4qUn2tt5

Yeah so, I missed that there was a ground to the battery, I wired that up, and now the contacts do spark when I bridge them with a screwdriver, and here's the thing, I've managed to get a spark a few times. It won't spark all the time, but I've managed to make it spark only a few times. I cleaned the contacts, stitched the leads to the ignition coil, but it is really inconsistent with sparking. I'm thinking it's kinda weak. Any advice on what it could be? I'll do a better test on the condenser tomorrow, could that be it? There isn't any sparking across the contactor