Tell us what color the spark was & could you hear it. It should be blue, loud [for a spark] & and jump about a 1/2" to ground. If it's lazy and yellow, it won't jump a 1/4". Does the spark look the same on 3 and 5 as the others ? If you have an ohm meter, check the resistance in the wires and cap assembled. They should all be relatively equal. To get it running well, I think you'll have to take a look at both carbs & elec. again but I think this specific problem is electrical, based on the info. Invest in Ztherapy's DVD on SUs[it's worth it & they're in Salem]. Plugs-NGK BP6ES. There has been some nice Z days this winter, at least here in the Pac.NW & you've got fantastic roads close to your home. Keep us posted, we want to see you on the road again too. Mark in Portland