The premium Garmin models for motorcycles would be the zūmo series.
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Some benefits are
  • GUI with large icons adapted for usage with MC gloves.
  • Premium models that have Bluetooth connection to headset or helmet with Bluetooth equipment. You can receive spoken street names etc. assuming that the Bluetooth equipment have the appropriate BT profiles.


From the zūmo 660 details at Garmin:
Keep In Touch

The zūmo 660 features Bluetooth® wireless technology so you can stay in touch while you're on the move. With it, you’re free to safely talk on your phone without having to remove your gloves or helmet. Simply connect your zūmo 660 to your Bluetooth-enabled headset or helmet and then pair with your cellphone to make and receive calls on the go. You also can call POIs through the zūmo’s Bluetooth interface — perfect for last-minute change of plans or a quick pit stop for food and fuel. And with spoken street names functionality, the zūmo 660 also will transmit voice prompts to your headset for wireless and worry-free navigation.

The new [Only registered and activated users can see links. ] is also a rugged multi-purpose unit that is useful for MC, trail, marine, car, geocaching etc.

Otherwise there's cheaper alternatives like nüvi 500/550 or the Dakota series plus the GPSMAP 60/62 series.