OK, Foreman Guru's I am working on a 2014 Honda Foreman 500 EFI electric shift for one of my buddys and while I am very familiar with working on ATVs, SidexSides and boat engines this one is giving me ****. The bike is completely stock, He is telling me that it ran fine when he parked it last season (about 4-6 months ago) goes to use it this season battery was dead so he changed the battery and the oil. Now it will start up and idle just fine but when you give it throttle it stalls/boggs and sometimes dies, give it throttle very slow it goes, but anymore then very slow you have the above problem also It does not mater if its cold or hot its always the same thing. It did have a code for the O2 sensor so I replaced it and cleared the code. Changing it only seamed to fixed the rich idle. So far I have (in this order) replaced the fuel with fresh new fuel, checked all if not most connectors to make sure they clean and dry,replaced Fuel pump and Fuel Injector, Throttle Position Sensor, Idle Air Control Valve, Tilt / Bank Angle Sensor, and the CDI / PGM, and still having the same problem and no other codes. I have also pulled the plug on the muffler and blew out any soot/carbon/rust build up. Fuel pressure is 53psi with key on engine not running. The only thing I'm seeing that I find questionable is while checking the fuel pressure with engine running I'm seeing it pulse from 53psi down to about 48psi while idling. Im assuming the pulse is every time the injector fires. Give it throttle it'll momentarily drop till about 38-43psi and will usually recover to about 48-50psi (If it doesn't die and you can get it past the stall point.). I'm wondering if maybe I got a bad "NEW" fuel pump/pressure regulator or if the Voltage Rectifier/Regulator is failing not supplying the correct or enough voltage. If you gents have any other idea where I can look for the issue it would be much appreciated.