Garmin Edge 800, Courses and Ridewithgps

GarryM

Had the Edge 800 now for a few months. Just wondering if anyone has any feedback on this particular issue.

I use Ridewithgps to create routes, then export a tcs file to my Garmin (New Files) which then converts it into a Course for me to follow. On the Garmin, I turn recalculate route off, lock to roads on and have audible warnings for turns and for going off course. The issue is that now and again it will remain silent on some turns (beeping if I take the wrong one - but that might take a few hundred yards) and sometimes it says I am off course when I know I am on the correct course - again a hundred yards or so later it beeps again to say it is on course - no problem if I know where I'm going but a potential nightmare otherwise.

I am hoping to rely on the Garmin for a ride across France in a month's time so this issue is a bit worrying!

Does anyone have experience of this? Are there any settings I'm missing? Is it related to the cue sheet on RWGPS - I had wondered whether I should laboriously click on every turn rather than letting it plot the route between clicks a long way apart?

All help gratefully received.

FoldingJoe

I think generally it could just be the accuracy of the GPS.

The signal strength you have is probably going to effect the accuracy, so if you are in a built up area it might be a little weak, which affects the accuracy, i.e. it can calculate your position to + or - 5 meters, or similar. What I would do is create cue points before your turn, so that Garmin will alert you before you get to it.

richh

It could be the above, but I think it's more likely to be that the ridewithgps file isn't including all of the turn points in its output. As far as I'm aware the edge 800 doesn't work these out on a course file that you've provided, and it only does this if you ask it to direct you home for example i.e. the edge800 is working out the course, not just following one that you've provided, therefore if the turns aren't in the file you won't get an alert.

I don't know ridewithgps but in bikeroutetaster you can see all of these points when you're creating the files and actually browse the turn-by-turn instructions and also edit them. I'd be surprised if ridewithgps didn't allow you to do something similar.

I could be completely wrong, but the above is the way that I picture it working based on using the 800 for a year now including a JOGLE.

Gizmodo

I use ridewithgps.com and a Garmin 800 (with Garmin's maps) and a friend that I ride with uses the same but OSM maps on his Garmin. We both get the same problem from time to time.

The problems as I can see it are:

1. The accuracy of GPS mapping on web sites vs. your Garmin. GPS is only accurate to about 4m. Add to that the fact that online maps such as Google Maps a series of data points connected with straight lines whereas in real life roads curve and bend, you will never get a true 100% accurate match between the map and your actual position on the road. Just switch ridewithgps to "Satelite" view and follow a road for a while, you will soon see the actual road and the plotted road diverge at times.

2. Road layouts change. Often I find that the Garmin says nothing because it thinks the road you want is straight on. But in fact some road planner has drawn white lines on the road to change the priority, meaning the Garmin straight on is now a give way and turn.

3. Ridewithgps exports a route that is not optimised for Virtual Partner. Their web site tells you that you should turn off Virtual Partner for your route.

I think the settings "recalculate route off, lock to roads on" refer to when you are using the web site to draw the route, nothing to do with actually when you are on the road. It is the Garmin settings that you need to get right to optimise the map.

On the Garmin I do the following: Menu -> Courses -> select the course -> click the spanner -> Turn Guidance=On, Virtual Partner=Off, Off Course Warning=On. I was under the impression that with these settings it is the Garmin that gives you the turn indications and the ridewithgps "cue sheet" is in addition. Using these settings, 200 yards before a turning the screen changes, shows me the direction with a big arrow and beeps several times. After the turning, I often then get a "cue" message from ridewithgps saying something as well.

When I am riding I have the map display page on all the time so I can see the way I am supposed to be going before the turn signal appears. Still occasionally I have to do a U turn, but the Garmin always gets me back on course by showing me the way.

GarryM

Thank you very much for the replies. I have created and followed courses over the past three days using RWGPS and with that experience and your comments, I am beginning to see how it works. If it’s of any help, I thought I’d post my findings.

The occasional and incorrect off course warnings do seem a bit random and as suggested that may be down to weak signal, the gps ‘line’ being slightly out of sync with the actual road or ‘none of the above’! Thankfully, each time it happened (probably only 4 times in 170 miles), I knew I was going the right way. Stating the obvious, but you still need to be aware of your route, surroundings, road signs, etc. so that you can judge whether you really are off course. Inadvertently, I did stray off course twice (at both junctions the Garmin offered no advice and I had not created ‘cue points’) and because of the false warnings, I did end up cycling further off course than ideal waiting to see if it was a genuine navigation error or a false one. Not the end of the world though.

When importing a RWGPS tcx file, like Gizmodo says, it seems to me the Garmin still generates its own turn directions as well as accepting the ‘cue points’ generated within RWGPS. The Garmin directions appear in good time as nice clear white lines on the map. Annoyingly, I can’t see a way of checking them before riding – they are always correct when they appear (IME) but they are sometimes absent. The RWGPS ‘cue points’ can come to the rescue here but I was amazed to see how many of these have the wrong instruction. Each cue point has an instruction and a comment. Many would say ‘straight on’ when the comment on the same cue point would say ‘turn left’. These ‘cue points’ generally appear just after you have made the turn/passed the junction (which may or may not have been very clearly advised by the Garmin instruction.) RWGPS lets you completely edit the cue points so that’s OK albeit a bit time consuming.

It would be really good to see the Garmin generated turn directions for your course on a web site so that you could see in advance whether it has missed any junctions – anyone know how to do that?

By the way, Gizmodo, although I’ve not experienced it, I always select ‘recalculate route off’ as I’ve read others describe how their chosen course has been cut short after taking a wrong turn as the Garmin then calculated another route to the finish point.

Gizmodo

GarryM wrote:

By the way, Gizmodo, although I’ve not experienced it, I always select ‘recalculate route off’ as I’ve read others describe how their chosen course has been cut short after taking a wrong turn as the Garmin then calculated another route to the finish point.

I'll have to try that one, thanks.

BTW have you tried the Garmin BaseCamp software for plotting a route? I can't get on with it but was wandering if if gives you any better idea of what the Garmin instructions would be on a route, given that it calculates the route from the actual maps on your device (rather than Google maps).

GarryM

Good idea. I tried several route planning websites inc. BaseCamp but found RWGPS the best for me. Having got used to that I've not given any of the others a second thought but I see your point with Basecamp so will give that another try to see if it identifies the Garmin turn directions (and where they've been omitted.) Thanks.