Peter, If you don't want to modify your bike by fitting indicators, there is an alternative. Flashing indicator GLOVES. I'v not seen any commercial ones but made my own many years ago, but the gloves are long since worn out and I never replaced them. With modern LEDs, batteries and flasher units it will be easier, but what I did (Mum actually )was sew a yellow light on the gauntlet of a pair of gloves with a small flat battery in a pouch on the gauntlet, and wires running down forefinger and thumb terminating in a small flat washer. I used to stick my arm out and create flashing by closing and opening thumb and finger. Crude but it worked. I have to say I did it in the 1950s when I went to and from from work in the winter dark, on a slow old 2 stroke Ambassador Popular. with glow worms for lights. Pitch black country lanes (I worked for The Forestry Commission). The only thing that hit me was a slow, low flying, Magpie which sort of "exploded" in a shower of black and white feathers and s~#t I wasn't "flashing " at the time as far as I recall!