Hi guys.
I searched but got no conclusive solution.
Please advise.

I parked the bike outside for 2 weeks under a flimsy cover. Its winter now, dry and no rain, ice or snow. Just well cold at night (3 deg). The bike worked perfectly. 2 weeks later and I want to start bike but NO electrics, no lights, no dash, no red led flashing, no socket power, no indicator, no clicking. DEAD. NOTHING. So I charged the battery overnight but nothing. I then (sort of) jumped the battery with a 12V spare car battery. The jumper cables were dodgy and old. But there was life! The lights, dash, circuit test and neutral all came on. Great!

So I pressed the starter button with the car battery still jumped to the bike battery and EVERYTHING went dead immediately. DEAD. I heard a sort of click disturbance like when the battery isnt connect properly. But I checked and rechecked all the connections and fuses. All seems ok. Now I dont know where to check anymore. I never have problems with bike. 😣

Can anyone guide what to do/check/test from here? Did I damage something in the jump? Is it ECU??? Rectifier? Should I have let the battery charge more bwfore I pressed starter button?

Ill appreciate any wisdom.

Thanks