Garmin Zumo 550 right now - but I have the new Zumo 660 on order, should be delivered the week of April 20th.

 

Zumo 550. Unfortunatly I have used more in the car than my bike.

 

just installed a nuvi 760, bought on ebay, remanufactured by garmin, 200 bucks delivered. hardwired in the fairing for power. also ran a patch cord behind fairing to the
aux input on stereo. using a ram mount on left handle bar. mp3,bluetooth. bought a 4 gig sd card. this thing has really impressed me so far..cant wait to take it on a trip

 

ZUMO 550. Built for bikes and comes with both brackets for car and bike.