That carb looks like a mikuni clone. The extra hose on the left side is a vent, you just need a piece of hose to loop downward somewhere out of the way. You'll need a threaded puller for the flywheel, dont try to use a jaw puller. Under the flywheel are two coils and a trigger. I doubt the coils are the issue, the trigger could be, but I'd suspect external issues (wiring, cdi box, ht coil, plug wire boot) before I suspected internal issues especially since the flywheel doesn't look like it's seen too much moisture.