Garmin Edge 800: An upgrade, but just barely, over the 705

I purchased a Garmin Edge 800 [1] over the holidays. As an avid 705 user, I was excited to see what the 800 was all about. Overall, it is a solid unit and will stay on my race bike. For many 705 users, though, I don't think the upgrade is worthwhile.

The Edge 800 is a top-end GPS equipped bicycle computer. My Edge 800 shows 1051 miles of use over the course of 65 hours in a month since purchase (Menu > History > Totals). In that time, I've become more familiar with the unit. My overall impression is that it is more pleasant to use than the 705, but not always more functional. I've noted some highs and lows, as follows.

Improvements:

- Vastly easier to calibrate a power meter.

- Larger screen, lighter weight (110 grams to 97 grams), very slightly wider and shorter.

- Vastly improved mounting system, using quarter turn lock (same as Edge 500).

- Touchscreen may be more durable. My Edge 705 has cracked seals on the buttons due to years of use. Some have joysticks that fail, too.

- Much faster processor: faster routing, faster power on time, usable map screen!

- Actually usable with topographic maps, like Garmin US Topo 24k

- Temperature support.

- Vertical speed field.

- Up to 10 data fields per page, up from 8.

- 3 data pages, up from 2.

- USB port is at bottom of unit - sits flat on desk

- Much easier to type thanks to touch screen.

- Unit is more streamlined and less likely to snag in a bag due to lack of touch stick.

- Ability to save workout files directly to external storage device.

- Able to copy custom workouts from 705 easily.

- Activities stored in more efficient .fit format - no need to regularly purge and compress bloated .tcx, faster uploads.

- Files are named according to local time zone setting, not UTC.

- "startup.txt" file allows me to put my name and phone number in while powering on the device in case it gets lost.

Regressions:

- Possible dealbreaker: No way to route using .GPX files. They all appear as courses, not routes. See https://forums.garmin.com/showthread.php?t=14186&page=3 .

- Screen is really hard to read in daylight due to reflective finish. Backlight helps, but unit drains battery really quickly with the backlight on high.

- On the power meter screen, the "Calibrate" and "Rescan" buttons are right next to one another. If you have fat fingers and hit the wrong one at the start line, well, no race data for you.

- No file transfer feature. With the 705 I could wirelessly send routes to other users. Not so anymore.

- Software automatically goes in "bicycle" mode when calculating a route. If I have a .TCX route that intentionally routes me on an Interstate (i.e. in places where the Interstate is the only possible route), bad things happen. What if I actually want the GPS to calculate a route using the car/motorcycle preference? I need to change the routing mode manually, every time.

- Still only reports as a USB 1.1 device with slow transfer speeds. There is absolutely no need for this. I have to pull the SD card to transfer map files, lest it take an entire day.

- Workflow is partially designed around Training Center, which is not good for Linux users. Uncompressed XML is bad for ride data but really good for creating content.

- Not compatible with .TCX courses or workouts. Requires an additional step through Training Center.

- No workouts included. I ported some from my 705.

- Garmin logo when viewed from the front is huge!

- Less internal memory: 128 MB (105 MB available) instead of 512 MB. Stingy.

- Garmin Training Center does not allow a user to directly import a .FIT file from a location on disk. The API is to ask the device for a .FIT file, which in turn, means that files have to be saved to internal memory and not an SD card. Seriously? Sure, .FIT files are smaller than .TCX files (uncompressed XML), but with less memory, it looks like manual management is needed still. This is a known issue, see https://forums.garmin.com/showthread.php?t=14537.

- The .FIT format is more prone to corruption, and less fixable. A developer API offers some Java tools to help fix files, but it is not perfect. I have already lost some important ride data due to a crash. For the investment involved in an Edge 800 plus a power meter, the acceptable amount of data loss should be "zero".

- Where did the date display go? With the 705, you can press the Power key and it will tell you the current day, month, and year. The Edge 800 has no date related fields.

- It takes more "key presses" to get to some features on the Edge 800, and since it is a touch screen, there is no tactile feedback. Of course, being able to quickly get back to the home screen by holding the lower left "cancel" button is a huge help.

- Keys are no longer backlit. That was a nice touch on the 705.

- Seal for micro SD card feels less robust.

- Seal for USB port actually IS less robust. I noticed some corrosion (blue-white stuff) after a rainy ride.

Notes:

- common firmware with Oregon series GPS. 705 was common to ETrex Vista series, 305 was common to other GPS.

- USB Mass Storage API like the 705.

- weird API for importing GPX and TCX routes using the "NewFiles" folder.

I hope that Garmin will address some of these shortcomings with future firmware fixes. The company does a decent job of getting products to market, but often lets them languish thereafter. For the cost of the Edge 800, us owners should be first-class citizens.

[1] https://buy.garmin.com/shop/shop.do?pID=69043

Solution to the PowerTap / Edge 705 Problem

You heard it here first! If somebody makes this and I don't get at least credit for the idea, I'll get lawsuit-happy!

So, here's the problem. I have a PowerTap SL 2.4, a damn fine piece of bicycle telemetry instrumentation. I also have a Garmin Edge 705, which ought to be quite a nice device, except for the fact that it can't read power data - at all - from my PowerTap!

In theory, this should not be a problem. Both of these devices communicate on the 2.4 GHz band and, with some cleverness and payment of royalty fees, I'm sure Garmin and Saris could happily negotiate either a software fix to the Edge 705 head unit, or a hardware change to the PowerTap itself. Rumor has it that this will happen this fall. I'm never one to believe rumor.

So, here's my idea. It's kludgy, and will take some work to implement, but I don't see why it's not possible. I'd like to build a wireless repeater device. Basically, this would function as a PowerTap head does, listening for the data from the PowerTap in real time. It would then masquerade as an ANT+Sport-compliant power device, and relay this information to the Edge 705! The device itself would be the size of a matchbook, run off a CR2032 battery, and probably have a little USB connector for programming the serial number of the PowerTap, or at the very least, a button and a red/green LED. It's a simple repeator-translator, nothing more, nothing less. It's a hack, partially technological, mostly political.

I was turning this idea over and over in my head, and thought to myself: is there any reason why this has to be restricted to the PowerTap SL 2.4 head? Why can't the regular ol' PowerTap SL do the same exact thing? Unlike the 2.4, which communicates directly with the head unit with a range of about three meters, the plain ol' SL communicates wirelessly with a smaller pickup, within a range of three inches, which then communicates via wire. Why not make a device that reads the SL data in real time, and also masquerades as a ANT+Sport power meter, for the benefit of the Edge 705? Not only that, but this device could also speak PowerTap, and basically upgrade a PowerTap SL to a PowerTap SL 2.4! You could even put a little magnetic pickup on the device, for regular old speed, and for kicks, give it the same shark-fin shape.

I tend to rant. I hope my proposal is clear. If not, perhaps ASCII art will work:

PowerTap SL 2.4 --(proprietary)--> PowerTap 2.4 head: this exists.
ANT+Sport device --(ANT+Sport)--> Edge 705: also exists - see the Quarq offering.

PowerTap SL 2.4 --(proprietary)--> Device --(ANT+Sport)--> Edge 705: my idea.
PowerTap SL --(short-range)--> Device --(ANT+Sport)--> Edge 705: also my idea.
PowerTap SL --(short range)--> Device --(proprietary)--> PowerTap 2.4 head: also my idea.

A single device can do all of this.

Definitions:
"Proprietary" - describes the 2.4 GHz protocol a PowerTap SL 2.4 uses to communicate with a head unit.
"short-range" - describes another proprietary protocol, of unknown frequency or characteristics, that a PowerTap SL uses to communicate with a wireless receiver, about three inches from the hub.
"ANT+Sport" - describes Garmin's wireless protocol.

I don't have any time to work on this in May, and I'll be on the road all summer. Perhaps I can work on this when I get back to MIT? The hardware should be trivial, I just need to be able to send/receive a 2.4 GHz signal. Any takers? Garmin or Saris, are you listening?

Edge 705 GPS: Highs and Lows

I've been using the Garmin Edge 705 GPS down here in North Carolina for the past few days on some rides. As I'm here to do basically nothing but ride, I've had loads of time to play with the device, trying to get it to do what I want it to do.

Here's how things would work in an ideal world. First, I would design a route for the day in DeLorme Topo USA 7.0. The route would be completely defined on known roads, and give me an idea of where the tricky climbs and turns would be. Then, I would take the route that I carefully drafted in Topo, and send it to the Edge 705. The Edge 705 would, in turn, let me know where the major climbs are, and where the tricky turns are, using its internal routing.

I've managed to shoehorn my desired functionality, almost. My original idea was to export the route as a DeLorme .GPL file, use GPSbabel to convert it to a GPX file, and send that to the device. I even used the filtering feature of GPSbabel in an attempt to limit the complexity and size of the GPX files I generated. However, for routes with over 100 or so track points, the Edge 705 would, after a while, choke with a cryptic error message: “Route Waypoint Memory Full.” It then crashed. It's running firmware 2.10, and I hope this gets better soon!

I've had better luck using GPX2CRS on the generated GPX file, turning it into a Garmin course file (.CRS), and sending it to my device using the Garmin Training Center application. This will give me a bright purple trail on the map screen that I can follow, and will let me know where the climbs are. However, I'm leery to use this method for a couple of reasons. Firstly, the Garmin USB Storage API still does weird things with course files. Where do they live, and how many of them can I have on the device? I'd like to have on the order of 100 different routes, all on the device, easily backed up, without having to worry about some arbitrary storage limitation. Garmin's Edge GPS devices seem to be hybrid devices: part traditional GPS, part strange undocumented API. Garmin, are you listening? I'd like to know how and why course files and their management are different!

My real goal is to use this thing on Intercity. That's 220 miles of riding. I haven't been able to get the entire Intercity route onto the Edge 705 without it choking somehow. Thumbs down.