Just bought a 2016 RSV4 Bike runs rough, speedometer not showing, low battery



Just picked up my 1st Aprilia 2016 RSV4 RF. Was a track bike with aftermarkets. I changed it all back to street fairings and changed out the Jet Prime LH mode switch and harness back out and put the street one back on with factory switch with turn signals, lights, modes, etc. also battery is coming back at 7.4v. Ill charge it on tender for 30 mins or so before test ride. Went to ride speedometer doesnt work, bike riding rough and wouldnt get over 20mph. Is this seem to be a battery or stator or any other issue before I fork out money on a battery