Speed Twin 1200 Indicator Issues

Does the left indicator work OK?

 

If both indicators are dodgy it might be worth checking the relay which should be located under the seat or side panels? There will be a number of relays and you need to try and identify which one is for the indicators. I take it the indicators are original and led?

 

If there is no relay it seems that the indicators will be controlled by the ECU with a flasher unit built into the instrument panel? Have you tried altering the indicator settings in the bikes menu? Are the indicators set to self cancelling?

 

Have a look in your Owners Manual. Download for free if you don't have one.
triumphtechnicalinformation.com

 

I would check the wiring on the left hand side of the headstock.
Your symptoms are very similar to the problems I had on my Street Twin. Open circuit supply to the speedometer.

 

From memory the speedometer has interaction with the indicators. Check the multi pin connector to the Speedo unit.
Also the stock wiring around the headstock is usually tight and ‘creaky’. It’s easy enough to gain additional slack around the headstock by moving the loom holder under the tank held in position by two bolts forward, after first elongating the vertical positioning hole horizontally with a hot soldering iron. However this is prevention rather than cure.Once the loom holder has been repositioned it’s possible to fit a matchstick between the headstock and loom, whereas beforehand anything the thickness of a Rizla paper wouldn’t slide between them