My 93 RS1100 flashes on start up then if you switch off and restart after warm no lights. I believe these lights are infamous for being temperamental
THE EXPERTS WERE WRONG!!!My 1993 R1100RS is same as Jimniven describes - also an expert told me it will always be like this.
Just overhaul replace the starter and also check the Engine earths
"OR" If you are sure the starter is spinning okay? Do the modification of fitting a relay to power the ABS up only after the engine is running and you will never have this fault again
Another benefit of the way I do the ABS Modification was by using the Green wire I was able to add a switch (Just break into the green wire and lead a twin core insulated wire to where you wanta switch) to Turn off the ABS if I was on gravel lanes or Mud
This became very evident I needed it after visiting an old friend and leaving down his lane I could not get stopped with road tyres on a muddy part (In the end I used the kill switch, a lower gear and the clutch as the brake lever !)