I have a puzzle whilst rebuilding my 1986 K100 RT with the indicators.
Having re-installed the original wiring I tested the indicators. The left indicators worked fine but the right failed to illuminate or blink with just a noise from the flasher unit. So my first reaction was faulty flasher unit which I replaced. Same problem occurred so probably not unit. The added conundrum was that when you switch the right indicator on the front parking light comes on tries to blink. I have consulted the wiring diagram and cannot see where these 2 wires would intersect to create a short or direct power to the parking light when right indicator is activated. To top it off the Parking light works fine when switched on normally.
Sorry for being long winded but any advice on where the fault could be would be gratefully accepted.
Rich

When was the last time you pulled the starter motor out and de-dusted it? Electrical goblins that have you scratching your head asking "howdeydodat?" are quite often the result of excess carbon dust buildup from the starter's brushes. It may seem an unlikely reason but that's no fairy story.

Not sure it is linked to starter as everything else works bike starts runs and stops front and rear lights including brake lights. It is just the right hand indicator. Completely puzzling me 🤔
Thanks for the suggestion I will keep an open mind
Rich

Yeah, when mine started to exhibit the same symptoms as yours the right hand indicator made my horns talk out of turn. Then the tail light got all disco ball-like. Finally when I pressed the left indicator button the dash lights would blink. I could have sat it in the middle of the dance floor, such was the light show. The starter did its job como Dios manda.

In an hour, after I was informed that the starter takes the electrical burden to heart, the fantasmas were exorcised.

Two Wheels Better wrote:. . . the fantasmas were exorcised.

Merry Fantasmas to us all!

I am going to pull the loom and will also give starter motor a refurb and see if that solves the problem
Thanks
Rich

Here's the pinout for the flasher relay.





If you remove the flasher relay and then put 12V to the blue/black wire's terminal it should illuminate the right turn signals and right indicator in the cluster. (The ignition does not need to be turned on to do this.) If that lights up the parking light too then you have a short somewhere. 

Otherwise your gremlin is most likely a dirty starter as has been noted already.

Replace fuse #7 as it will cause as much havoc as a cactus starter. Don't just pull it out and look they can be corroded internally and be open circuit and still look good.