Garmin 780

. . . you might have a bad power source or internal battery.

The 780 rocks - it (and the 760, which is the same but for the car plug provided) was the last of the 'good' navigators Garmin produced, but as a motorcycle navigator it does have some limitations.

If you don't feel like waiting on the phone contact Garmin Support by e-mail.

I have never had any issues with my 780 at all.

Why would Amazon not exchange the second unit?

Why get another that does the same thing??? The unit is not designed to be used on a motorcycle...

They would not exchange the 2nd unit because it had the same basic issue as the 1st.

What's the difference whether it's a car or motorcycle? They both have wheels that go down the road.
My inclination now is to see if amazon will exchange the 780 for the 855. This will allow me to use voice commands while riding the bike.
Advise please

There are lots of differences between an automotive and a motorcycle unit. First off is an auto unit isn't exposed to the weather, the moto unit is weather resistant so a little rain doesn't bother it.

Second, a motor unit is built to handle the vibration while an auto unit doesn't get near the same levels.

And third, a voice response unit? Do you think you can shout louder than the wind noise blowing directly into the rear facing microphone on an 855? Do you honestly think it would understand you? I have a hard enough time getting mine to understand me when in the car, and cracking open a window or playing the radio at the same time - you have to be kidding.

I agree with a_user about using voice recognition on a bike ... simply won't work with the built in mic on the nuvi. You might be able to get it to work if you use a closed helmet and external noise cancelling mic. The 855 cradle does have a microphone jack. But even then I think it will have problems with background noise.

This may come in handy, so you can 'talk' to your 855 while riding:
http://www.radioshack.com/product/index.jsp?productId=210403...

Well, I ride a Goldwing which has very little vibration and I use the FM transmitter to push the music, and road commands back through my helmets headset and mic. I had no problems hearing the music and voice commands with the 780 and one complaint I've read says that the voice can barely be heard on the 855 until they changed to the program(written by that GREAT GUY that everyone on this forum should be proud of TurboCCC)TTSVoiceEditor. Now if I rode some of the other big bikes, vibration would surely be an issue.
As far as the weather is concerned, there is a waterproof case that can be obtained for the 780. Not sure about the 855 but yes, that would be a concern.
Unfortunately, the Zumo models start around 600 and just keep going up. They say they are water resistant, not water proof.
I do appreciate all your advise, thanks.

Thanks Chew, I appreciate the positive feedback ;>)

Directly from the garmin website...Vibration-tested, waterproof and built with fuel-resistant plastics to withstand the elements

I run a nuvi 780 on a my bike with an inexpensive bar mount I got off eBay. Been using it for almost 2 years now with no problems at all. And I've put it through hell... -6F to 105F, 4 times unprotected in the rain and the back is always plastered with squished bugs. It sure sounds like you have a bad power source, power connection or ground.

http://img39.imageshack.us/img39/3619/picture049f.jpg
http://img40.imageshack.us/img40/3757/picture040b.jpg
http://img188.imageshack.us/img188/3464/picture043a.jpg

Thanks Seapup for the info. Nice bike by the way.
I notice the last picture has view of the Sat status. I never could find that screen??

I've tried 2 different power cords with the same results. I thought the unit was ok. Took it around and it was working fine and then I ran it on the batt for about an hour. I then brought it in the house and again hooked it up to external power. It wasn't long before it started to dance back and forth between charge and the 'External Power Lost' screen. It did that until I shut it down.
I boxed it up and sent it back to Amazon and ordered an 855. So I'll go from there.

In addition to the aforementioned issues of weather resistance and vibration, the Zumo (motorcycle version) is glove friendly, left hand friendly vis-a-vis buttons and switches, and the bluetooth is helmet friendly.

Except for the Nuvi 765 (so far) all of the other Bluetooth enabled devices only pair up to phones.

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Edit: ooops, I see you have other experiences on motorcycles. Mine include glare problems and keeping an eye on the road, so I opt to listen to directions rather than following the mapping itself.

And yes, the Zumos are way pricey. I've opted for the 765 and an earbud (it has an audio jack) but the sound is low on battery, so I'll have to relent and wire it, and myself, to the bike.

That I can help you with.

It's accessed from the "satellite strength bars". Touch the screen over the bars (for about 2 seconds or so.)

The unit freezes up to many times
is there a solution to solve the problem with the unit.

I bought my nuvi 780 at costco the unit freezes up
return the unit to garmin the same problem