Motorcycle Repair: 1984 Honda VT700C, shapei, reserve tank

Question
I need help in troubleshooting a bucking problem on a VT700C.  First, a little background info.  The bike sat for 5 years.  Has 3900 miles on it.  Ran great in 2003.  The first thing I did was pull the carbs, disassembled them and thoroughly cleaned them. Diaphrams are good and jets and pilot screws were in good shapeI did not split the two carbs and did not touch the sync screw.  I reassembled the carbs and reinstalled.  I flushed the fuel tank and reserve tank and changed the fuel filter and any questionable fuel lines.  I also changed the spark plugs and cleaned the air filter.  I poured some sea foam in the tank and topped off with fuel.  The bike fired right up and idled fine after a minor adjustment.  It has good acceleration throughout the power band although it rumbles a little at 5500 RPM when holding the throttle steady and then pretty clean up to almost red line.  Then I hit the street with it.  It runs beautifully for the first mile then it begins to buck as if it's being starved of fuel.  If I let off the throttle momentarily and hit it again, it recovers but starts the bucking again. I tried applying a little choke but had no effect.  My fuel pump appears to be working.  I can see it kicking fuel through the filter every half second to second.  By the way, should the filter be full of gas?  It only fills up about 1/3 or the way.  I checked my gas cap and the vent seems to be working fine.  I also checked the atmospheric vent from the carbs and it's open and properly routed.  If I let it sit for 20 minutes or so, same thing.  Runs great then starts bucking.  I'm confused.

Answer
If it a very sharp buck, it's probably ignition.  It could be a coil heating up, a plug wire or boot or the ignition modules.  You probably have a high voltage leak to ground somewhere. There's no easy way to find it that I'm aware of.

Regards,
Rich