Smart Phone as your main device

[ROADHOG]

how are you logging mileage ?

try using the Narrative on Silver City to the Interstate with Google Maps, Google Earth or Garmin Topo.

[Long Haul Greg]

Hello All,
    For TD-13, I had my smartphone prepped with the .gpx route, but I used the ACA maps and my old-school cycle computer's odometer for primary navigation.  I prefer to use the mileage cues and do mental math as I ride.  Battery usage is just one aspect of the GPS units, whether stand-alone or smartphone.  A couple other vulnerabilities to consider:  I crashed hard, real hard, on a rocky descent near Sand Mountain, about 30 miles north of Steamboat Springs.  My body position got too high/forward in one stretch of rocks and I went over the handlebars at speed.  My phone was on a secure mount, but that ended up being the first point of contact with the rocks, crushing the phone at the top of my aero bars and rotating the entire handlebar assembly down about 60 degrees.  My turn-by-turn map cues became the only navigation for the remaining 1,500-ish miles to Antelope Wells.  It wasn't really a problem.  The only time I was a bit concerned was my first morning in New Mexico, making my way up towards Brazos Ridge.  The "road" gets pretty primitive and I was concerned that what I was experiencing wasn't matching my mental picture from the map cues.  I just kept climbing and was rewarded with the huge vista Brazos Ridge offers.  Plus, I caught up with a couple guys who were navigating by GPS, so all confidence was fully restored.
   
    Another planning consideration:  Last year, we had two major fire re-routes.  That's no problem with the odometer and cues, but it could be a problem if your navigation plan is to simply follow your pre-planned .gpx route.  Recall 2011 had a banner snowfall, so there were major re-routes in the early snowbound areas of the race.

Bottom Line:  The GPS units work and the ACA maps/route mileage are accurate.  If there are real-time detours, you're going to get alternate routes and distances to factor into your navigation plan.  Be sure you can adjust accordingly, whether doing map/compass dead-reckoning via cue sheets, or .gpx GPS navigation.

[ROADHOG]

What about tire slippage and inaccurate OD numbers ? Are you resetting the second OD to zero at ACA turns ?

GPS resolves 3 fork problems . ..

Carrying electronics in a waterproof crashproof box with antenna up is standard procedure for rough rides where falling or hitting a tree is possible.

When you get THERE, check the GPS and check for battery health, related issues.

I use the GPS for ongoing entertainment finding that unnecessary on steep rocky cliff side down hills.

I was lost once for about ten  minutes on hills above Cades Cove.....there's a clearing or was radiated with 5 paths. Whooooaaaa ! I did not immediately ID the way back...it all looked the same. A few minutes of subconscious dredging brought a walk down the second try back to recognition.

One problem in that vein is past history. My regular ridge history runs SW to NE...out of that environment probabilities increase for NOT knowing where you are for where you want to go.

Figure ACA couldn't survive multiple mapping blunders....they'd get lost !

[sfuller]

What about tire slippage and inaccurate OD numbers ? Are you resetting the second OD to zero at ACA turns ?

I might buy inaccurate OD numbers, but when using a regular computer, I tend to set mine via rollout. They might be off a little bit, but not enough to make me worry too much.
Tire slippage is generally not an issue as for a dumb cycle computer, I put the sensor on the front wheel.

I'd guess my mileage would be off more just from the occasional off route excursion for food/water/camping than anything.

[ROADHOG]

Your experience is that if ACA sez take the goat track left - of 3 available - 2 more in the next 3 miles -

at 32.6 miles, the cyclometer pins that 32.6 down so there's no problem  with 5 available choices ?

I assume ACA avoids this problem...but how ?

How many trail riders use and do not use GPS ? Have an opinion ?

Retro activities or avocations/hobbies/attitudes even lifestyles abound then Ultra-lights...in canoeing and kayaking there are gourmand groups hauling bake and dutch ovens.

I guess hauling a dutch oven could pose as large a problem as not using GPS.