I have a Nuvi 660 and bought a Ram Mount for it. The unit works well except powering it is a problem as the supplied cigar charger only mates with the car mount (suction cup). The power plug on the unit has a smaller connector which you can charge with the 110 adaptor directly without the mount. Do any of you know a way to directly power the unit while on the bike?

 

Try this website for some ideas:

http://www.powerletproducts.com/

 

You should look for a stepdown. I have a magellan crossover that I ordered a setp down harness for. It steps the power down from 12 volts to the 6 volt requirement. direct connect to the battery.