The 60 series takes AA, not AAA.

After using a Garmin Edge 705 for tens of thousands of miles, I can tell you that the screen is perfectly adequate. It's too small for a car traveling at 60mph, but for a bicycle you can zoom in on the map and it works fine.

The battery issue is over-stated, I think. I tour near civilization and haven't found recharging to be an issue. If you leave your battery-powered GPS unit on for the entire length of your ride, like you'd typically do with the Edge, and I suspect you'll be going through quite a few batteries. If you're resourceful, you can find plenty of places to recharge a Garmin Edge. Stopping for lunch at a restaurant and plugging the GPS in while I'm eating a sandwich is my favorite strategy. Arriving early at your campground and asking the host to plug the device in for an hour or two before they leave also works well.

If you're using a GPS which takes AA NiMH batteries, you'll need more than a couple of hours to recharge them. It's why I take plenty of spare batteries and also a battery charger.

Sorry keyboard stutter. :)

We can agree to disagree then. Even the 60 is too small IMHO. I don't know how many times the routing feature has taken me out of my way or around in circles. A bigger screen would make it much easier to see the intended route. If you marry it with a paper map then the screen is probably OK.

And I'd much rather just swap batteries when I need to, instead of worrying about finding a place to recharge or remembering for that matter.

As OP I've benefitted from the comments that have been posted to date. As I see it, the consensus is 1) GPS's can be helpful 2) battery life restricts their usefulness 3) GPS's are not a practical alternative to a cycle-computer 4) paper maps are the most reliable navigation aid.

This being so, let me ask the following; I am planning a US coast to coast trip in the next couple of years and will, by and large, follow the ACA routes and use their excellent maps. By necessity, their maps have quite a narrow focus and it seems to me that the chances of having to divert from their route (because of road closures caused by flooding or maintenance) and thus off their map appears quite high. So alternative maps will need to be carried (and I have a couple good ones for NY state - produced by the NY DOT - which will be my starting state). Now given that I don't want to have carry too many with me but, rather, pick them up along the way, what maps are best, and where can they be obtained?

I have been considering a tablet PC combined with a GPS. Of course you still have the charging problem but would have every map you needed. If you are going coast to coast then you might want to consider a dyno hub or solar panel for charging needs.

many smart phone GPS applications let you pre-load map data so no cell coverage is needed.

I have had ZERO luck with this.

On the Trans America, I found it easiest to just pick up a state map in each state to augment the ACA maps. I sometimes traded maps with someone going the other way if I met them near a state line. Alternately I either gave the state maps away when I left the state, mailed them home if I was sending stuff any way, or discarded them. The ACA maps I kept, but mailed home the ones I was done with.

Some states like Kansas were a grid of rectangles for much of the state and you didn't really need the state map. If a road was closed just move over one.

BTW, if asking directions... Most locals are pretty bad at directions, but if you manage to ask a professional truck driver, odds are you will get amazingly accurate and detailed directions. That has been my experience any way.

If you have a newer and higher end GPS (and a means to power it, given the potential issues of carrying chargers or lots of spare batteries) they support custom maps. That lets you put your own maps into it by geotagging them in Google Earth. I recently did a four-day tour with some friends, and the guy who organised it put some custom maps into his GPS (mine is older and doesn't support them) to guide us through the areas where we found the signs lacking last time we did the route. So for most of the way we had a track log I'd set up and for the trickier parts we also had a more detailed map with our planned route drawn on it.

I know that's not exactly what you were asking, it's just an option to leave you a little more prepared before you set off, if you've got the budget (and inclination!) to buy a high-end GPS in the first place.

MintyBoost is a AA powered usb charger. The Garmin 705 only recharges when plugged into a usb cable, it can't be operated while plugged in. I haven't used a MintyBoost, but it's supposed to be compatible with Garmin GPS devices.

My Garmin 705 recharges in less than an hour from my PC usb after 4 or 5 hours of use.

http://www.adafruit.com/images/mediu...yboost_MED.jpg

If you use paper maps, almost every convenience store (stores that sell gas, soft drinks and snack foods) sells state maps.

In a few years GPS units may be cheaper and better so don't rule that option out yet. You might even consider a car type one that does not work on the handlebar but they are cheap and have up to date maps for emergency use when you find a road closure.

Good story. I also recall reading of a European family that was suing a GPS manufacturer because the turn by turn directions took someone through a dangerous slum that was controlled by drug gangs and he was killed.

Back in the day, on REALLY long trips I only ever used a road atlas. No Google maps, no GPS. Just maps. Crazy, right?

There are also a number of pre-built alternatives to the MintyBoost. Googling for "USB battery back" seems to turn up a number of alternatives. Some use standard AA batteries, others are larger-capacity rechargeable batteries, etc. I haven't found the need to purchase one of these devices, but they seem like they might be a good alternative for those who are paranoid about power...

This is my experience as well, though I use the wall-charger more often than the PC.

Portable Power for onboard GPS
 

As Amoxicillin says ".. a device you can connect to a hub dynamo and use this as a power source to run the gps as on a power line. it serves as some sort of electric transformer and is called e-werk. it's available from a german manufacturer, Busch & Müller."
Here is a link to the U.S. distributor of the eWerk: http://bit.ly/iqcuOI

There are also many solar charging devices that will charge your toys (if it's sunny, of course).

As for powering a AA gps, I've found that with normal use, disposable lithiums last a loooong time. Easily justifiying their extra cost. For me, normal use when touring is maybe a couple of riding hours/day.

Recharging the 705 battery at c stores, restaurants, and campgrounds should rarely be a problem. No more so than for a cell phone. A USB battery pack seems like a reasonable and simple backup.

As for navigation with a gps, I map out my route on www.ridewithgps.com using the road magnet feature, and download track files to the eTrex thru Garmin's Mapsource. About 100 miles/track. Just follow the track. I think the eTrex will accept about 15 one hundred mile track segments done with the magnet feature. This is more for fun than practical reality. I always use paper maps for the big picture. I let the gps function normally for turn by turn routing thru large towns and to find points of interest. Or ask x3 and hope.

Longer, less precise, track segments can be plotted and downloaded with Mapsource or Basecamp, as there is no magnet feature, thus fewer plotting points.

Actually you can create extremely precise routing using City Navigator® North America NT (or other areas) and Basecamp which will exactly follow the selected roads curve by curve. Worked great on my 705. They have also dropped the price of the map by $20 from last year.

Back in the real day, real cavemen did not even use a road atlas.

The reason why TomTom on the smartphone is sweet is it requires no cell coverage, all the data is stored client side and the positioning is done solely with the GPS satellites.

+1 for iPhone GPS for navigation. But I also alway have a paper map with me. No need for cell covage with a decent smartphone unless you need to load maps. For this reason Googlem Maps is not the best app since you can't store maps. I have serveral other apps that allow me to download the maps and those work great. I have also been happy using cheap backup packs that cost only $5 each. They will take my iPhone 4 to a 90% charges per pack. I carry 3 of them with me most of the time.

As I build out my touring bicycle a dynamo hub and larger backup batter will keep my iPhone charged.

I can't justify another gadget to get a dedicated GPS unit with the performance I am getting out of my iPhone right now.

A word for Garmin phone service here. I have found it to be exellent. English speaking folks who will stay with you 'til the problem is ressolved.

The eTrex will not process a downloaded ROUTE file properly for turn by turn directions. Neither will most other handhelds by Garmins. Exception, according to Garmin and some on here, is apparently the Edge 705/800. These units, by option I guess, will not recalculate a downloaded route file, but will follow it precisely the way the user plotted the route on a mapping service, or on Basecamp/Mapsource. This could be a huge consideration if you want to plot routes outside the unit and try for turn by turn directions. Otherwise, you're limited to tracks.

Is this the experience of you 705 users? Can you download a route from a mapping service and get accurate turn-by-turn instructions?

It has worked for me using Basecamp/Mapsource.

It also quickly alerts me when I have gone off route.