Most drivers are expecting turn indicators to be very close, if not beside your headlights. You canít expect others to scan your rig for other locations. I noticed the blinkers youíre referencing on the mirrors but seriously.....they may be quite visible to you because theyíre close to you, but theyíre not as bright as you might expect for other drivers because theyíre not looking there.
Also....I was a Motorcycle Safety Instructor for years, and always advised the students that the size and brightness of most motorcycle turn indicators are too small and not bright enough to catch the attention of others. They might be more visible at night, but almost invisible during daylight hours, so I always advised using hand signals when possible during the day.
As another suggested, I would look into installing the brightest and largest LED turn indicators on the lead edge of the rack. Canít hurt.
Ken and Terry
2018 Sunseeker 2430S-CD carried by a 2017 Ford E450
Former Georgetown 330TS owner for 10 years with more mods than I can count.