Review on CBR 600 F4 F4I Carbon Mirrors: Top-rated for 2005-1999 Models by Jaymai Alford

The end of the rod goes into a slot in the base, with washers on the sides to fill the slot and screw everything through. Well, haha, joking: they don't deliver enough pucks to even come close to filling the gap! You can tighten it all you want, but you'll break the base before it stays in place at speeds over 45 mph. Instead of breaking the base, just add a few more thin stainless steel disks until it's semi-tight and limp. some blue Loctite and tighten it. Considering you have to spend a buck or two on some flimsy stainless steel washers to get it working properly (and Loctite, but you still need it), otherwise it's great.