Recently I made new Extension plate for KTM 690 Enduro Luggage rack SD. One of the features is bent side flanges. This enables easier access to slots on the flange. Also, it adds strength to the Extension plate.
European and US bikes have different licence plate holders and rear turns signals. Here is my 2016 Euro model.
Turn signals on US models are mounted higher. They are also bigger. I was aware of that, but since I don't have US models around me, I made wrong decision about bend angle, so side flange of Extension plate touch rear turn signal on US bikes.
Telerover did great video, explaining the issue.
On all new Extension plates this will be corrected.
For bikes with Euro plate carrier or aftermarket turn signals, like the one on the picture bellow, this is not an issue.