Some bikes just don't have a nice location for mounting accessories. For this purpose, Givi makes a neat little accessory mount, providing a short section of Ø22mm (7/8") bar for GPS/smart phone holders, or whatever else you need a clamping spot for. Designed to mount under the mirror, clutch clamp, fairing bracket, or where ever it fits.
Available as a single item (S951KIT2), or a pair (Z278).
