Join Date: Feb 2020
Location: Upper Bucks County Pennsylvania (east side of state)
I'm new to the forum, but hopefully I can help. I have an '09 KLR 650 with Tusk Pannier Rack. I took pictures to go along with the info below, but I do not see a way to post them (there is a reason I like a simple motorcycle). If someone can educate me, I will try to post them.
The turn signal extension piece is just flat steel stock .182" (3/16" will work) thick X 1"x 4 11/16". There are no bends, but there are four 5/16" holes (larger than needed), and a radius recess to clear where one of the rack tubes is welded to a mounting plate.
The Tusk design eliminates the rubber vibration dampeners in the KLR frame that the turn signals normally mount to, and replace them with shaped pieces of steel .234"thick (1/4" will work). These mount behind the frame (wheel side) where the rubber pieces originally were. They made these with nuts welded on as it is kind of difficult to reach inside the frame. If I were making them, I would just tap them. They are a bit of an odd shape, but you can just use the rubber insert as a pattern for the shape & to align the holes. You can use that same rubber insert to align the holes on the flat extension piece by placing the rubber flush with the ends of the plate. I do think the shaped pieces inside the frame are needed as the turn signal mounting method (steel frame cutout & rubber dampener) was never intended to support all that much weight.
If you can get access to the original Tusk installation instructions, it might save you some frustration. The turn signal wires are not long enough to reach to the new signal locations, but if you re-rout the wires under the seat, you only need to extend the one side.