sounds like a lectric problem. check the battery ground too. back in july you had this problem? you made no mention of backfires. when your sickle ratted out the polished 96 S&S cylinder on that chopper back in sep07 seems to me that is when weirdness set in. June 08 your throttle grip needed to be slid on the handlebar. you had the bike dying on you in July. for some reason you used seafoam in august. and now POWWWWWW! it could have taken that long for the neg ground cable to work loose to the point of your current pow. stealers working on sickles for weeks is scary.
your sickle is loosing spark then regaining spark. thus the pow. i would say check your float heights but fat is fat. it'll still run. and if it doesn't you'll see the gas puddle... intermittent loss of spark? grd cbl, coils, halls, puter.
Fuse box. did you pull all the fuses and grease em up? yes you did replug the coil connectors. were they tight? did ya grease those too?
check (meaning grease up) the connectors in the headlight bucket.
rework ALL the lectric connections all of em i say. right down to idle accessory plug. well maybe not that far.
don't loose sight though. start with the negative cable, then the solenoid connections.
