I have a 420 es that wont shift ouy pf neutral. The battery died because I had a boss speaker on and left it on one day by y accident . When I jumped the bike it wouldnt shift with the buttons only with the emergency tool I can mess around and get it to shift sometimes with the buttons but not right bv st all.when I press shift buttons the shift motor sometimes sounds like it tries to switch then sometimes shift motor doesn't do anything