yep, do it every year on my motorcycle, every other on my scooter (S200 is a pain in the a** to get to the master). So much easier to do on a scoot or bike vs a car (but your car needs brake fluid changes, too!)
My helix had nasty, sludgy fluid that was almost empty in the master...flushed it all this summer, will do it again when riding season is over.
I also like to pull apart my calipers and clean and lube the slide pins at least every other year.