My new to me 1100 displayed the same ABS symptoms (both lights flashing together when the ignition turned on and then when when the starter button was pressed the clock reset and the ABS wouldn't initialise - both lights flashing alternately). No amount of charging etc fixed it, but I knew my battery was probably dead, so no surprise.
Just had my first decent ride since fitting a new OEM gel battery - everything worked fine - ABS initialised, clock didn't reset etc. I'd bet your battery is dead.
PS - When I took the old battery off (wet cell type), it had about 1" of acid in it - another good reason not to fit wet batteries to our bikes - such a faff to check and top up the level that no one bothers.
Just had my first decent ride since fitting a new OEM gel battery - everything worked fine - ABS initialised, clock didn't reset etc. I'd bet your battery is dead.
PS - When I took the old battery off (wet cell type), it had about 1" of acid in it - another good reason not to fit wet batteries to our bikes - such a faff to check and top up the level that no one bothers.