I have a 2004 gsxr1000 that will not start. I stored it through the winter.It started and ran good but had loss of power over 8000rpms but otherwise started and ran. I sat it for 2 days and now it wont start. It is turning over and getting fuel but I'm thinking its not getting enough spark. I have changed plug, air filter and cleaned the fuel filter. Whats wrong?

moved you out of cars to MC
suzuki

if rpm stay same [not bogging ] then check drive belt if good add new fuel or a little booster fuel may cause power loss also

charge and test the battery. the battery may be no good after sitting all winter and may need to be replaced.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/kelly_69a0cf1b13789df1

Your starter is bad or the teeth meshing on the gear is to loose.

the map code may be a symptom, not the problem. I would have a shop that specializes in VW check it out. Auto Zone isnt much help unless you are buying oil or car wash soap.

check fuel pump relay or fuel pump, run scanner for trouble codes, some auto parts stores do this for free

bad ecm relay replace relay or swap relays in the ipdm

At first blush, sounds like corrosion on the battery cables either at the battery or at the other end at the alternator or starter. There are several sprays at the auto parts store that will clear the corrosion but the best way is to remove the cables and clean both the cable ends and the posts. Once you're able to rule out the cables/connections having the charging system checked would be next point of order but its more likely to be the cables. A car that won't run on it's own isn't getting enough power from the alternator so I'd check the negative cable first.