If you have a single indicator bulb on the dash for the turn signals, it back feeds the other side when you have one side on. Many guys have a trick with 2 diodes that fixes it.
www.superbrightleds.com
Metric Bike Diode Kit | Super Bright LEDs
Required when installing LEDs as turn signals on motorcycles with single turn signal indicator light. If Diode Kit is not installed, power will back feed across the indicator light and all turn signals will flash at once. Price for each.
www.superbrightleds.com
