After fitting new battery on my fjr 1300 Drove a
Have your charging system looked at, first do a simple multimeter test, get a multimeter, switch it on to Volts, start bike and see what it reads, put multimeter prongs directly on battery, very simple, if its below 12V you have a charging problem. If your battery is new and your charging system is faulty the bike will start and go, but when you switch it off the battery will be dead because it has not been charging. When you let a dead battery sit for a while it will charge itself a little, enough to start the bike up. Have you ever had a flat torch or mobile phone, it will die when battery is flat but when you try and switch them on again after a little while, they will work a little and die again, same with bikes, cars etc. All the best, Forever Two Wheels :)