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Discussion Starter #1 (Edited)
i gave it shot today 2-#4 washers as shims with a 120 mikuni main jet and 3.5 turns from seated on the pilot mix screws. with the the stock pilot jet. wouldn't even run with those settings it was seriously starving for fuel, it would just race up for a couple seconds then sputter out and die, it seemed like the hypercharger wasn't creating enough vacuum in the venturi's to pull the fuel through, it like the stock air cleaner choke's the carbs more to pull the fuel. there's probably enough fuel available but there's not enough vacuum to suck it through the jets
 

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Discussion Starter #3 (Edited)
does the HPC connect to the stock airbox.the HPC cannot let in more air than the stock airbox, unless it going down the road and being funneled in.
all hyperchargers connect to the stock airbox on a 650 of course it let's more air in when idling because it uses a K&N full flow filter, i even held the butterflies closed to any excess air and it still acted like the engine was starving for fuel, even on choke it would race up for a second and die, it was like the fuel was available but there wasn't enough vacuum in the venturis to suck it in to the cylinders, i tried various PMS settings 3 turns out to 3.5 turns and even 4 turns out and nothing worked i even tried blocking off the front of the charger to create more suction, it would not run no matter what. i took the shims out reset the screws to 2.5 turns with the stock air cleaner it runs perfect again. i'm at a lose here. i'll sell the whole hypercharger with shims a 120 jets for 100.00 if anyone wants it. 12.00 shipping and its yours,someone on this forum must have did a self install on one of these, i'd like hear how they got it to work right, the one i have uses the non thunder adapter from the air duct to the charger, it still uses a fitting to the fuel bowl vent hose and a vacuum line from both manifold nipples to the diaphragm that controls the butterflies, i still say there's a vacuum loss in the venturis because its too free flowing
 

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Discussion Starter #4
does the HPC connect to the stock airbox.the HPC cannot let in more air than the stock airbox, unless it going down the road and being funneled in.
now i'm seeing vastly differing info on pilot jets some say use the stock pilot fuel jet then barons says use a #35 pilot fuel jet and kuryakyn says a 22.5 pilot fuel jet is needed those numbers are numbers a too far apart to be useful. and no one speaks of the pilot (air ) jet which if you go smaller will create more suction on the pilot fuel jet, which might help with the lower vacuum situation that i believe is happening.
 
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