Won’t start … 2002 Boxercup!

[BoxerCup02]

After some help / advise please. Bike been sat since October and regularly on Optimate 3SP trickle charger. Started first time on Monday and took for an hours run no problems. Put back on charge ready for MOT next day and when returned in morning, strangely no red light for Datatool alarm? Turned on and all lights up but nothing from pressing the starter. Can hear fuel pump prime OK, checked all fuses and no issues. Also swapped out battery for new as old Odyssey battery from 2012 (good innings!). Still same issue and won’t start? Feels like alarm / bike immobilised issue? Any suggestions? Have home start with insurance as an option!

[ianbcr]

Have a check of the earth to the frame as they do get corrosion on them and that will be a non start issue. I had that issue but got a clicking on the button like a flat battery. the connection is by the battery on the left side if I remember correctly.