First check batery terminals are tight, but as you tried substitute battery unlikely. Good Earth on earth lead? Next I would look at Kill switch / switch gear and / or micro switches IE inhibitor gearbox, side stand if fitted etcHi all, hoping you can give some advice.
Few days ago I tried starting my 2005 F650 GS, but it wouldn't even turn over. I heard a faint whining noise (hard to tell, i had earplugs in... was ready to ride) but definitely no turning over. The water temp light would continuously flash until i attempt to start it and it stops. Also noticed the digital clock or odo seemed to say "bat", so I assumed the battery needed charging, so did so.
Still nothing, most of the time it makes no noise when i press the start button, lights etc do dip a little as it would when normally starting. Doesn't say "bat" on the clock or odo anymore. I did try swapping for a known good battery, though its exactly the same.
Any ideas what might be the cause, or what I should be looking for to find out. Appreciate any help!
Some extra info; the bike probably hadn't been run in about a month or so, but stored in a fairly dry shed. I've had issues in the past where water would get into the switchgear and make it tricky to start etc. but i don't think that would be the case here! Also i can hear the fuel pump priming when you turn on the ignition.