Some thoughts on GPS options for randonneurs

Submitted by Peter Grant:

2013 was a record year for me. I used more types of GPS than ever to ride brevets.

I started riding in March with an old and trusted Garmin GPSMap60Cx purchased in 2006 and repaired once shortly afterward. In 2006 I had navigated using routes planned on Garmin Mapsource and then downloaded to the GPSMap60Cx. Mapsource routing took me interesting places and added bonus kilometres which were not always wanted. I spent untold hours checking routes before switching to tracks from previous years rides. In recent years I have been following tracks from past years or new ones that I have learned to synthesize with Google maps.

In May this year, David McCaw visited to see if I could fix his GPSMap60Csx which had started switching off on road bumps. I make the fix by opening up the gadget and soldering 2 pieces of #30 wire from the battery pins to the printed circuit board. The operation is a bit fiddly and time consuming so I loaned David my GPSMap60Cx and set his aside until I got time to open it up.

I had a Garmin Edge 800 and had been planning to use it some time anyway to try to learn a reliable way of getting turn prompts. So, for the Foymount 400 and then Devil Week I used the Edge 800. The Edge 800 has a built in battery that only lasts about 200 km so I also connected an EWerk to power it from the Schmidt hub.

June cycling was great. I loved Devil week except for the Edge 800. The Edge 800 display is very difficult to read under many lighting conditions. With the GPSMap60, I never used the back light. A quick glance down at the reflective display was enough to confirm that the arrow head was in the middle of the screen and on the black track line. Not so on the Edge 800. A quick glance often shows only a black rectangle. I shift my hands and then 1 tap on the touch screen activates the back light. Another glance to check if I am on track. Ok? Yes, but sometimes I have tapped it twice in a sensitive spot and it is deep in a programming menu. It is easy to retreat from the menus since that needs tapping in the bottom left corner, but my main interest is actually on the road. The pavement edge, the wheel in front and the car at the next intersection all interest me much more than the touch screen. Sometimes it puts out little white blocks with dark squiggles of micro-printing in them. Younger eyes might find the Edge 800 more informative than I do. It is almost an obsession for the Edge 800 to display micro-printing and chirp as I reach the centre line of an intersection. What I want is a chirp between 90 and 110 m before the intersection. At that distance I can see the turn. I am getting old, but my short turn memory is not that bad yet.

Did it improve my navigation? Not really. I made a number of wrong turns. I had carefully programmed course points 100 m in advance of each cue and made a tcx file. The course points were displayed, but no chirps generated. Chirps instead occurred in the middle of intersections were I ignore the gps in preference for watching what the traffic is doing. After an intersection, I could do the screen tap bit to see what it was trying to tell me. Often however, if I had missed a turn, another rider was yelling at me and saved the trouble.

Not getting the prompts that I want is all my fault I am sure. I should spend enough time experimenting with menus and configuration and it will start to work. But, as the season progressed, David needed another gps and I passed the Edge 800 on to him.

On returning from Devil Week, I bought an Edge 200. It was cheap, had a mono display, had 4 buttons and could not use maps. On a few local rides it worked very well with my tcx files. The display was the best I have ever seen on a Garmin product. Low resolution, big letters, high contrast, no confusing map lines and it seemed to reliably generate advance turn chirps from my tcx files. So, after only a few trial rides, I used the Edge 200 on the Lac Megan tic 600 on July 6 to ride where I really have not gone before. It worked. There are some annoying details in the way it scrolls the distance to next cue, but it needs much less configuration than the Edge 800.

The built in battery is one of the limitations of the Edge family. I was using the EWerk to power the Edge 200 and as we returned to Montreal we were caught in a short downpour. Shortly after that, the Edge began to announce “External power lost” and then external power restored at each road bump. The roads on entering Montreal produced plenty of these events. The same EWerk has done this before only after a combination of rain followed by a bumpy road. A friend suggested that a water drop was inside the electrical works somewhere and each time it bounced around it caused a short and then removed it. I do not know. But the next ride was approaching soon and I decided to use a gps with throw away batteries for London-Edinburgh-London.

LEL provided gpx tracks which were exactly what I needed for a Garmin GPSMap62s which I had planned as a replacement for the GPSMap60Cx. Before leaving for the UK, I downloaded an Open Street Map UK map that a UK cyclist had prepared with cycling and footpath overlays. In the GPSMap62 these overlays worked very well to help us navigate in unfamiliar territory. We followed the tow paths, horse trails and cycling routes between Loughton and Tower Bridge. For this type of riding, cycle touring and not brevet riding, the maps were essential to letting us go places we would not even have tried to go otherwise. On the actual Audax ride it was better to turn off the maps to make it easier to see the display. The GPSMap62 display is usable in reflection, but not as good as the GPSMap60. It is semi-colour. All different shades of pastel. I use yellow tinted sun glasses which protect from the sun but also provide good visibility in dawn and dusk. The Garmin colour display lines become various levels of dirty grays. So, turning off the map and following the only line visible works for me.

For the LEL ride, the GPSMap62 worked fine with the tracks provided. There is a lot of memory in some of the new units so many routes can be loaded at once and at LEL I actually used tracks I had simplified. I simplify the tracks to less than 500 points per segment for friends who used GPSMap60Cx and it didn’t seem right to provide other people with tracks unless I used the exact same ones myself. Keeps me more honest when I write my scripts. Older Garmins truncate tracks at 500 points. I discovered this the hard way years ago when I still relied on Mapsource. They do generate an information message, but the message occurs when a USB cable is plugged into the Garmin. Since the USB plug is on the back, the GPSMap60 lies face down on the floor when I download to it. Only my carpet sees the TRACK TRUNCATED message and out on the road my track ends far from the control.

The GPSMap62 has improvements over the GPSMap60. It has a follow track function that makes the track a wide purple line on the screen. On the GPSMap60, the track is a narrow line that can easily be confused with a map line. Still, there are wide road lines and it is possible to confuse the purple line with a road when I have tinted glasses on. Since I always wear glasses while riding, it is better to set the map detail to minimum or even disable the maps completely.

The GPSMap62 handlebar mount looks like it will be harder to break than the GPSMap60 handlebar mount. However, it does not hold the GPS unit on the bike very well. On LEL it started launching the GPS at most road bumps after a few hundred km. There was no lanyard in the box when I got the GPSMap62 so my ever resourceful wife manufactured a tough nylon lanyard, looped it through the slot on the GPS and sewed the ends together. That keeps the unit with the bike but having to haul the unit up to see where I am is an annoyance. A small zip tie looped around the mount and over the GPS just above the zoom buttons worked well for me on LEL. With just the right tension on the zip tie, it could be wiggled down over the buttons to allow getting the unit off for battery changes about 3 times on the 1400 km. The mount for the Edge series seems to be a great improvement. It looks simple, but in 5000 km I have not lost an Edge. Unfortunately, there is no slot for installing a lanyard on an Edge. This leaves me uneasy since in years of using Garmin handlebar mounts as well as a RAM mount they have all failed.

On the 4th day at LEL the GPSMap60Cx which David was using started turning itself on, booting up and then switching off before acquiring any satellites. Then it would switch on again and repeat. It probably got water inside during a battery change.

Here is how I navigated the Granite Anvil 2013 using an Edge 200. To program the Edge 200, I combined the tracks for each day and created 4 courses, 1 per day, using gmap. This is because there seems to be a limit on how many courses I can have in the Edge 200. I stored the resulting files in the directory Garmin/NewFiles. The Edge 200 converted the tcx files to fit files when powered up. Each morning I selected the appropriate course and pushed “Ride”. Each evening I saved the activity. After the ride the Edge 200 showed 2 Mbytes used, 3 Mbytes free of its total 5 Mbytes.

To power the Edge 200, I bought a 3000 mAH li battery, a Power Pond, at MEC. It is about the size of a skinny chocolate bar and has a charge level indicator and USB connectors. With the USB cable plugged in, it jams into the bottom of my Bento box. When fully charged, the Edge 200 draws 30 mA with the back light at minimum or off. Thus, 3000 mAH should give 100 hours plus 10 hours on internal battery. The first night at Midland, the Power Pond showed about 1/3 used which is about twice what I had expected. Since we were in a hotel with drop bags, I just got the charger and recharged it. Even with 1/3 gone at 400 km it should have been enough to last the ride, I should not have been so concerned with power. We had no rain on the Granite Anvil so I do not know if this will survive a wet ride. I pack the electrical connections with clear Vaseline which might help keep water out.

On the Granite Anvil ride we also developed a new (to me anyway) technique to disable a GPS. Or make it useless had we been on a long ride. The USB connector on the Edge 800 sticks straight back when it is on the handle bar. David was using an AA battery pack to power it and at some point the back pointing connector caught on his Bento. The connector part of the cable broke leaving connector bits inside the USB port of the Edge. At the hotel that night the broken bits came out easily. But, the battery pack end of the connector was proprietary so we were left with a good battery pack and working Edge 800 but no cable. I had put 2 chargers in the drop bag so we just plugged that gps in as well.

As we progressed around the Granite Anvil loop, David several times mentioned that the Edge 800 was not working right. It chirped at all side roads but not at my course points. The mounts are exactly the same so at some point along a quiet road section we swapped units and I tinkered with the menus. I had disabled the map but that seemed to only disable display of the map. I do not remember any more what the option to chirp at course points was called, but I found it eventually. The chirp at every side road was called “something guidance” I think. The first time I proposed that he could have the high priced gadget back I thought that he hadn’t heard me. A few minutes later I said “Do you want to swap back?”. “I can see this!” he responded, referring to the Edge 200. A minute later he commented “This things working perfectly”. It is not just me getting old I guess, so are my friends. I got the 200 back at Durham College and David bought one of his own shortly after the ride.

The Edge 200 is much more useful than the Edge 800 because it seems to be more automated and has intelligent defaults. When following a course it always auto-scales, something that I usually dis-like, but on the Edge 200 it seems correct. When you start to follow a course it auto scales to show where the course is relative to where you are now. It seems to be quite sharp at recognizing when I am on course and rarely signals a false off-course. The Edge 800 is a bit sloppy on both accounts. When on course it zooms in to a 200 m scale which is a bit close, but one of the display options is to show distance to go at the bottom of the screen. This displays the distance to the next turn and counts down as I proceed. Someone should have stopped the programmer there, but he went on to make the display flip between distance and time. Time he calculates from the virtual partners speed in the tcx file. So on my downward glance to see if I am on route I do see the track ok but about 50% of the time the bottom field is showing the pseudo time rather than distance. The size of the numbers is about as small as I can resolve so it takes a few glances to see if my next turn is 100 m or 10 km away. I have set the virtual partners speed to be the minimum ACP speed so if he passes you, you are over the time limit.

As I approach a turn I have a feeling for the distance to go because of the countdown display. As I pass the course point, the Edge 200 chirps. At that distance, the geometry of the turn has become visible at the top of the Edge 200 screen and the course point is at the bottom of the screen. That is how it works with a pre-warn distance of about 100 m. In gmap, the 100 m is calculated from where the cue balloon appears which is almost always at an apex in the graph. If I take the wrong road then the Edge 200 chirps again and turns the bottom line of the display to inverse saying off-course. It starts auto scaling to keep the course visible as I ride the detour. If I get back to the course, it figures that out and continues. In the tcx file, I do not leave a course point right at the intersection. As I mentioned earlier, I do not want distractions in the intersection. If the Edge 200 does chirp in the intersection, it means that I just made an error. When conditions are safe, I can look down and see where I am relative to the track and then get oriented for the correction. I think that I got the Edge 800 to work this way once, but it takes more steps.

Sometimes cues are closer than 100 m in complicated intersections and around controls. Gmap does not move a course point if it is a control nor will it move a course point past another cue. It starts at the end of the track and works backward. Usually the last point is a control so it stays put. The previous cue is located and gmap tries to move it back towards the start. If it can be done without passing another cue it does so and then tries the previous cue. If there are several closely spaced cues you will get lots of chirps but the shape of the next 200 m will fit on the Edge 200 display and it can be figured out.

Now, in mid-winter, I am making route changes and fixes for the Randonneurs Ontario route archive. The course combining that I used for the Granite Anvil was on not line last year. It is there now since I have been revising the site. The old file formats are still available but tcx is more prominent. Hopefully this will make navigation simpler and more reliable for riders. I have been revising routes for Devil Week 2014 and have 1500 km of great cycling lined up. We will be seeing more of the beautiful Ottawa valley and lots of the granite hills that surround it. Hope to see you here.

Peter Grant