My 1996 BMW R1100R has blinking ABS lights. I have changed the battery and I understand I have to reset the ABS.How do you do this.

There are a number of comprehensive solutions for the BMW R1100 on youtube. Just search for "BMW Service".

there are two quick discon. rh side unplug and remove tank

On each wheel, there is a sensor with some wires attached to it just behind the wheel assembly. Odds are one of the wires is worn out from the elements as they're all exposed.

Please don't just pull the bulb because a faulty abs system can cause serious injury

i have had this a couple of times, when they have diff trouble etc i take them to a place covered in shingle on concrete. when i figure of eight them around so everything is working hard i can detect which diff or what ever is wrong.
now when u do this for a certain amount of time, (some differ) u have to understand what happens, when round a roundabout, the wheels closer to the roundabout are turning slower, outter wheels faster as they have further to travel, this abs traction control are programmed to see it.
when u figure of 8 it gets mixed up, i have had three now had them reset and bingo. I know your abs sensors are fine as light goes like u said. the most expensive bits are working.
also i would like to add, i changed a battery on 1, the owner claimed the same prob. u have to bear in mind she could be pulling a fast 1. anyway i had it reset at my own expense as could not reason with hear, it was cured.
so there is other things there somewhere that up sets it, if u keep on figuring 8 it this does.