Incredibly slow route calculation - Garmin Edge Explore

You are right, disabling the TBT prevents the initial calculation of the TBT Course overlay and TBT messages table and lets you start your ride nearly immediately.

Recalculation is a different thing - this is intended to bring you back on your course when you have deviated from it for whatever reason. However, don't expect to keep your original course unmodified after a recalculation. My experience is mostly that recalculation calculates a completely new route to the destination. Therefore I always set Recalculation Off.

Yes, you're right. I have that off too. The calculation that people mainly complain about is the initial calculation when the route is first loaded - before turning everything I could off, disabling all maps but one and uploading via Connect, it would take 20-30 minutes of valuable cycling time before it would finish 'calculating' and be ready to navigate.

Thanks bikepc01 and  8296360 for the informative response. Here's my standard operating procedure when using the Garmin with pre-programmed routes.

1. No peripherals -- phone, bluetooth, etc -- connected. Just the unit itself, usually on battery saver mode.

2. Thus far I've only been using routes I've created in Garmin Connect that've been sync'ed to the Explore via Garmin Express

3. I always refuse to 'navigate to start' as the few times I've opted to it's proven such a debacle. I just start riding and have the Explore calculate the route while pedalling. For 100+KM routes it can take quite a while. 

3. I **do** use Turn by Turn as that's the prime reason I bought the unit.

As for the pre-loaded Garmin maps I was hoping to gain some insight into what each map does before experimenting--hoping to save some time. I'd rather just ride and I didn't include optimizing the Garmin to a practical level of responsiveness to be part of the purchase price. But I may have to dive in...more gizmo distractions.

From what I gather all maps are supplementary with the exception of AMR Standard Basemap. What I'd like is a unit with basic (turn by turn) navigation and responsiveness.

I guess the only thing you can do is to go back to an earlier version of the firmware, at least before 5.20, at least as an experiment. In the same situation I would go back to version 5.00 or maybe even earlier.
If you use courses generated from external sources (Basecamp, Mapsource, RWGPS, etc., etc.), use only TBT navigation with a few sensors like speed/cadence and hrm, no CIQ, no connected functions or other 'advanced' functions, then the Explore may be completely useful for your purposes.
I'd give it a try, because the very long initial calculation times at load of the course seem to be introduced with the latest software updates. Sorry that I cannot give you the exact version when that occurred...

I have the same problem.  Did you find a solution?

Could it be that setting a route up on the computer uses Google maps, but then when it's downloaded to the device, there's a different set of maps.  Even if there's only one metre of difference between the two then the device goes through the routine of re-calculating?  Could it be that? And if that's the problem, how do I use Garmin connect with the same set of maps as my device?

SteveNewcombe said:

Could it be that setting a route up on the computer uses Google maps,

Just try it yourself for once.
You can also create routes with Openstreetmap on Gamin Connect.

The annoying recalculation problem does not exist interestingly with the GAMRIN watches.
I can start my planned route from any point and as soon as I am directly on the route, the navigation starts immediately.
So it must be something in the software.
Memory (Cache) management?

I know nothing about Garmin watches but if you turn the recalculation option to OFF on the Edge Explore that's also what happens. That is, just find your own way back back to the route; when you do the Edge will recognized it and it's business as usual.

I recommend just leaving the recalculation option permanently disabled AND the Off-course notification enabled. That way, if you want to detour or wander off-course for whatever reason you'll know the Explore has acknowledged such and you'll not interpret its unresponsiveness to any malfunction. Not recalculating probably also saves significantly on battery life. Further, I always opt to NOT be guided to the course start when loading a saved course.

After a couple of years with the device I don't have solutions. I have workarounds. The at least allow adequate, if unimpressive, performance from the Explore. You should reconcile yourself to its limitations: it's just too underpowered to practically deliver on the options engineered into it, a case of marketing overreach.

Let me be clear: the Explore is a disappointment but that doesn't mean it's not useful. Used it yesterday for 130KM ride, 11 hour day, and no problems. 

Here's my general setup for Explore.

• Route recalculation: OFF. I find no need to enable it; the recalculations are so glacial that the feature is basically unusable. If I deliberately detour off course I already know I have; if I miss a turn I'm immediately notified and that's enough. Wander back on course yourself and the device will recognize you're where you're supposed to be and resumes where it left off within a dozen seconds.
• Wake up device when off course: ON. I always run the device in Battery Saver mode so most of the time the Explore is asleep. If I ride--intentionally or not--where I haven't plotted in an active course then the Explore lets me know immediately. 
• I use the Explore only for navigation, typically in sleep mode. All connectivity shut off except GPS. No Bluetooth, ANT+, widgets, sensors, etc.

There it is. There are thousands of KM's on my Explore. I find when riding long courses, over an imperial century, I often have to re-boot the device when it fails to wake up from sleep or becomes unresponsive. Battery life will last me over 12 hours; that's in battery saver mode so the display wakes only the unit is issuing TBT guidance, as opposed to simply recording a ride; and all other connectivity/features/widgets are disabled. 

If you need extensive performance telemetry as well as GPS route guidance and recalculation in a practical, performant package IMO the Edge Explore is not the unit for you.

Unfortunately, my final "solution" was to exchange it for Edge 530 :(