Motorcycle Repair: 1983 honda shadow vt750, valve stem seals, fuel pump relay

Question
i recently purchased an 83 honda shadow vt750. after riding the bike for about 5 or 10 mins. the bike begins to bog down and eventually stall out. while the bike is bogging down the right pipe sounds much louder than the left, in fact i can't hear it at all. when the bike is first started a thick white exhaust flows out of the left pipe before calming down after warmed up. not sure if any of this could be related. carbs were just taken in and rebuilt by pros. gas was drained and replaced w/ new. coil packs replaced. new plugs w/ good spark. air filter clean. can i be positive at this point its a fuel flow issue? i have yet to replace the filter and check the lines but i'm wondering if there are any other possibilities as i'm not so sure where to go from there. thanks so much!

Answer
Andrew, it sounds like the bike is running out of fuel. The thick white smoke is oil which is probably worn out valve guides or valve stem seals leaking oil into the ports or cylinder. When it first starts to loose power try putting on the choke. If it picks up a little it's fuel related. If it doesn't change anything, it's probably ignition.  It could be a fuel pump or fuel pump relay not working or it could be a plugged fuel filter.

Regards
Rich