Super Jet SJ bog?

Location
Oregon
This is only a minor problem, but I just got my first SJ, it's a 2000 and it is in great shape. Only mods are a shred master ride plate and a prop that I'm not sure of the manufacturer. The issue I'm having is the engine bogging down when I mash the throttle. If you just take it easy and ride around then hit the throttle it will bog. If you keep after it there is no bogging issue. Am I looking at an accelerator pump issue? It seems that it is jetted correctly but maybe the accelerator pump can't push fuel in quick enough on the initial throttle hit? I had this issue on my Yamaha YFZ450, and fixed it with the zip tie mod to make the accelerator pump move instantly with the throttle linkage. Any suggestions? I've never had these carbs apart.

Thanks in advance
 
The stock carbs on superjets don't have accelerator pumps. Assuming you've got stock carbs on there, I'd pull them apart and look for crud in the internal fuel filter (it's on the fuel pump side of the carbs). Also, while in that side, look to see if the clear white discs are intact (not wrinkled) on the carb with the fuel pump.

If it's not crappy/old gas, a gunked up on/off/res switch, fuel filter, or the internal fuel filter, then a general carb rebuild may be in order...assuming the carbs are tuned correctly.

If there's no head, pipe or anything else that would require non-stock jetting or screw settings, then definitely compare the jetting / # of turns on the screws to the stock settings below (copied from '96 manual):

Main jet: 130
Pilot jet: 70
Lo speed screw: 7/8 turn +/- 1/4
Hi speed screw: 1-1/8 (F), 1-1/2 (R) +/- 1/4
Needle & Seat: 1.5

..and go from there. Hope that helps.
 
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