Garmin Allow Recalculation

I get asked a few questions about how to plot routes and transfer them to Garmins, so I wrote a couple of blogs on the subject

Garmin 705

Garmin 800

However, the problem I’ve noticed most with routing is caused by the same “feature” that people inadvertently have enabled.  If you think about a car satnav you tend to put in a destination and then follow the route the device calculates for you.  If you take a wrong turning you rely on the device to recalculate the route and still take you to your destination.  The default behaviour for Garmin bike satnavs is to do that too.  However, if you plot a circular route where you start and finish from the same spot, that doesn’t really work, because as soon as you go off-route your Garmin will calculate the quickest route back to the start.  


So if your main use for your Garmin is based on circular routes you plot yourself then make sure you set this option (found in the routing or navigation options menu) to either off or prompted.  If you set to prompted you will be given a dialogue box if you go off-course.  If you do not select NO then it will timeout and default to recalculating.

Hope this helps

Garmin Speed/Cadence Sensor Problems

The Garmin GSC10 speed/cadence sensor sits on the chain stay and has two “sensors” that record both the stroke of the pedal (cadence) and the rotation of the rear wheel (speed).  The sensors are in fact reed switches that are activated each time a magnet passes them.  The cadence switch is, I believe, in the body of the GSC10 and the speed switch is in the arm.

So I have three of these things on each of my bikes and have not had any problems.  Tonight on my commute home my Garmin started auto-pausing whilst I was moving, recording a 0mph speed.  This was intermittent at first but then just stuck at 0mph.  The cadence was recording correctly which meant that the unit was successfully paired with the 800.  When I got home, I tested it further using the small test light on the side of the unit, which flashes red when the pedal passes and green when the spoke magnet passes.  The red light was showing but no green.  A change of the battery didn’t help, nor did repairing the device.

So a quick search on the Garmin forums identified yet another common problem.  Yes, another.  It seems the reed switch in the arm can fail.  It’s not easily replaceable (of course some have managed it) but as my unit is several years old I’ve decided to bin it and just use the GPS from the 800.

So if you get some more strange behaviour on your cadence sensor then this might be your problem too.

Garmin Update

As predicted by many on the forums, Garmin have replaced my faulty chest strap without any fuss whatsoever, which is great service from them.  However, it does point to this being a known issue that they are aware of.

A further update on my experience of the polar strap that I am currently using is that this is a very comfortable strap (more so than the Garmin) and so far there appear to have been no issues or problems with it from an accuracy point of view.  The only real difference is that you need to dampen the contact points before wearing.

Hope this provides some useful information if you are starting to see spikes or irregular readings with your Garmin.

More Garmin Woes…

Ade's Road Cycling Blog

A strange thing happened the other evening on my commute home.  The heart-rate alarm went off on my Garmin.  Now I’ve been reading fellow cyclists blogs and tweets talking about heart-rate based training – basically riding in zone 1 (50%-60% of max heart-rate) and zone 2 (60%-70%) to aid fat burning.  I struggle with staying in these zones at weekends so have resolved to try and do it on my commute instead, which is easier to control on my fixie.  Anyway, the alarm goes off when my heart-rate is above 190bpm!  And I was pottering along at a very easy pace.  Looking at my Garmin the HR was registering in the high 180’s and 190’s.  After quickly discounting having a heart-attack, I adjusted the premium heart-rate strap in an attempt to correct it.  In fact it went up to 225bpm – see graph above.

I’ve done a number of experiments now with the strap and have concluded that it is faulty.  The problem is repeatable but unpredictable – you can ride for some time with a seemingly sensible reading and then it will spike upwards.  But it is consistent in that it now happens every ride.  Sometimes it reads 155bpm without the strap on.

A quick search on the Garmin forums and the internet proved the issue is not unique to me.  It seems that plenty of people have reported the same problem.  Note that this is the premium Garmin soft strap with the transmitter that clips onto the front via two press-studs that comes with the 800 (I think also the 500, 410 and 310 but I’m not sure), and not the hard plastic fronted one that come with the 705 or 305.  It seems that Garmin will replace the straps – so I’ve contacted them and we’ll see how that gets on.

In the meantime the threads suggested that a better solution was to buy a replacement strap from Polar – the Polar Wearlink+ strap.  It uses the same press-stud connectors and the transmitter from the Garmin just snaps right on.  The Polar strap is good quality and more comfortable, and so far my real-world tests have proved that it is reading sensibly.  The strap itself was £11 or so from Wiggle and well worth it, regardless of whether Garmin replace my original strap.

Hope this helps if you are noticing erratic Garmin chest strap HR readings.

Here is somebody else’s findings on the subject in a bit more detail, including pictures of the relevant items.

Garmin 800 file transfer tips…

A while ago I posted a Beginners Guide to Routing on the Garmin 705 which was to help people create a bike ride in a site like Bikeroutetoaster or gpsies and then transfer that to their Garmin.  I also posted some first thoughts on the Garmin 800 in this post, and also some more on files in this post.  This following post is a little bit more information on some of the file structures and also the different process to transfer files on the 800 to the 705.

Mapping Sites

Ade's Road cycling Blog


Ade's Road Cycling Blog


I’m not going to go into detail about transferring a ride from one of the mapping sites, as that is covered in my beginners guide post mentioned above.  The sites I use have the option of transferring the gpx file directly to the device, if you have the Garmin Communicator plugin installed.  However, from time to time you may wish to use the alternate method to save files to your computer and then transfer them manually to the Garmin.  The two screenshots above show how you do this in bikeroutetoaster and gpsies – by selecting the file option.  This will save a gpx file, always called course.gpx regardless of the name you give it, to your downloads folder.  If you are doing more than one, remember to rename the file to something else.

Garmin File Structures

The following screenshots are taken from a Mac, but the structure will be the same on a PC but the windows will look different.  Here’s the root directory

Ade's Road Cycling Blog


An interesting difference to the 705 is the documents directory which if you open it will contain a file called START_HERE.html.  If you double-click it you will see the following screen open in your browser

Ade's Road Cycling Blog


This screen gives you access to the user manuals that are stored on the device itself.  If you click either of the links it will download the manual to your computer or open the pdf file.  A useful feature that means you always know where the manuals are if you ever want to refer back to them.

Back up at root level if you open the Garmin folder you will see the following

Ade's Road Cycling Blog


On the 705 you would copy your downloaded gpx file into the courses folder.  However there are no gpx files in the courses folder on the 800 – they use a new file format called .fit files

Ade's Road Cycling Blog


On the 800 do not copy your gpx file into this folder because it will not appear when you turn your 800 on.

Ade's Road Cycling Blog


On the 800 you copy your gpx file to the Newfiles folder.  The next time you turn on your 800 it will automatically convert the file into the .fit format and move it into the Courses folder.

Additional Features

If you go back up to the Garmin folder you will see a file called startup.txt.  You can edit this file if you want to display any text when you switch on the 800

Ade's Road Cycling Blog


You can see a number of lines in the file.  The important ones are the display line and the message line.  In the example to the left I have set display = 3s which means my message will, surprise surprise, be displayed for 3 seconds.  My message is Garmin 800 – Ade Hughes, North Cheshire Clarion, but you can put whatever you want in this sentence.

A second interesting feature is one I mentioned in my previous post about the 800.

Ade's Road Cycling Blog


In the Garmin folder is a sub-folder called Backgrounds.  There is an option to set a background picture (wallpaper) on the device in MENU->Spanner->System->Display->Background, and the device has a number of pre-populated images in there.  These are 160×240 pixel jpg’s and you can make your own.  Here’s one I created from a photo of myself.  You simply save the jpg into the folder and then select it through the device as mentioned above.

Ade's Road Cycling Blog


One final thing.  If you look at the side of the box the 800 came in you will see a screenshot that shows a 3D map much like those you get on your car satnav.  If you are wondering how to get your map looking like that then MENU->Spanner->System->Map->Orientation and select Automotive.  You should get 3D map view with that.  If not then in the same option menu set the Automatic Zoom to OFF.

Hope that all helps…

Tan Hill 200 Addendum

I forgot to mention that with the tremendous hills yesterday came some brilliant descents.  These were real point-the-bike-and-hold-on-for-dear-life drops, and I broke the 40mph barrier on 12 (yes twelve!) different occasions, maxing out at 51.8mph!

Also, when the total ascent went over 9999ft I discovered a bug on the Garmin 800.  It justs displays “—-” even though it correctly records the ascent.  Bizarrely, total descent displays fine over 9999ft.  So if this happens to you it’s “normal” – I have reported the bug to Garmin so we’ll see whther that gets ironed out in the next firmware update.

Garmin 800 2nd Impressions

I’ve now done a number of rides using the Garmin 800 and have some further observations.

  • The first of these is the automatic timer start feature. There isn’t a Garmin 705 owner out there who hasn’t stopped the timer (by pressing the stop button – not auto-pause) at a cafe or mid-ride stop and then ridden off forgetting to start it again. Losing 10 miles of data in the middle of a long-ride is one of the rites of passage of owning a 705, but the 800 adds a setting that detects movement and asks if you want to start the timer. Simple, but very, very useful.
  • What were called saved rides on the 705 are now called courses on the 800.  There is a search facility such that if you have a lot of stored rides you can quickly find the one you want.
  • When calculating a saved route it is much quicker than the 705.   The UI is improved too. Again – helpful if doing it on the move.
  • The training partner feature helped me knock 30s off my personal best in the Kilton time-trial. I simply set training partner to an average speed that would beat my PB and then attempted to beat my training partner. The display shows time and distance you are ahead/behind him, which is really useful – it makes pacing yourself easy with a graphical UI.
  • The 800 allows you select a background picture.  These are 160×240 jpg’s and are stored in a folder and therefore you can add your own.  Here’s one of my ugly mug – see picture
  • You can also add startup text and duration it is displayed.  There is a .txt file in the root directory and if you open that there are instructions in the comments.  Mine now says “Garmin 800 – Ade Hughes, North Cheshire Clarion”  Possibly useful if you lose it and an honest person finds it?
  • There is a screenshot function allowing you to capture a screenshot by pressing the power key briefly – see picture

    Ade's Road Cycling Blog

    Custom background captured using screenshot function

  • The beep warning you of an upcoming turn is not as loud as the 705 – which means it is difficult to hear especially if moving fast or on windy days. But the increased screen size makes the display clearer to see and tricky junctions easier to navigate.
  • On wet days, wiping away the drops on the screen can cause you to switch screens inadvertently, although you can lock the screen.
  • The covers for the USB and microSD slot don’t especially fill me with confidence – although the unit is claimed to be element-proof.  We shall see.
I’ve also found a particular issue if uploading rides from the Garmin 800 to Rubitrack on the Mac.  It’s not a big deal as there is a simple workaround to do with un-mounting the map card before sync-ing.
I’ll keep posting more on the 800 as I discover things.

Garmin Edge 800 – First Impressions

I’ve finally bitten the bullet (what on earth does that mean really?) and bought a Garmin Edge 800.  I’ll probably post more about it over the months but here are my first impressions

  • It looks a whole lot more modern that the 705.  It’s smaller and more compact, yet has a larger screen.  An extra tenner seemed worth it to buy the silicon sleeve and a touchscreen screen-protector.
  • In the box are the usual things – 2 bike mounts, heart monitor strap, map card, cadence sensor, charger, usb cable and NO MANUAL.  This is contained either on the Garmin website or on the device itself in a documents sub-directory.
  • Plugging into my Mac, first impressions were not good.  The Mac did not recognise the device and therefore didn’t mount it.  Great start.  A quick google and it seems this was a “feature” with v2.1 software.  Turning the 800 off, holding down the reset button and plugging it into the USB port forced the Mac to mount the device.  Garmin updater then updated it to v2.2, which does allow the device to be recognised.
  • It features a new sub-directory structure.  GPX files are dropped into a “New” directory and automatically converted by the Garmin.  Hopefully this should make transferring plotted rides easier but that remains to be seen.
  • The touchscreen is good and allows space for more data than the 705 on the training screens – up to 10 data items.  However, on the map screen it only allows up to 2 data items as opposed to the 4 I had on the 705 map screen.  Don’t understand this as the screen estate was smaller on the 705 and was still usable.  A welcome addition to the data items available is the air temperature.
  • The 800 features a new twisting bike mount that feels a whole lot more secure than the 705 cable tie mount.
  • Out on the bike it performed as expected.  The screen was visible in differing light and the additional size of made the map easier to follow; the route guidance working well.
So my early impressions are good.  The 705, despite its quirks, provided great service navigating me all over the country for thousands of miles.  Hopefully, the 800 will do the same.

Beginners Guide to Routing on the Garmin 705

A few people in the club have recently got Garmin 705 bike GPS systems and have struggled a little bit with some of the features.  It’s fair to say that the manual is not helpful.  So this post is a very quick and hopefully simple guide to basic setup and routing on the Garmin.

First up is how to transfer a route from a route planning site like bikeroutetoaster.  There are plenty of sites out there that do this sort of thing, including mapmyride and gpsies but they all follow a similar process.  I’ll use bikeroutetoaster in these examples.

bikeroutetoaster map page

If somebody sends you a link to a gpx file and you click it, invariably it will open in a screen like that shown above, with the route overlaid on a google maps interface.  Similarly, that’s what you’ll have if you have plotted the route yourself using the tools in the frames (boxes) on the right.  In the top left corner are 4 tabs.  Clicking on the Summary tab will bring the following screen up

bikeroutetoaster summary page

There are 3 frames on this screen showing the Course Details and the Elevation Chart, and also a Download frame.  In this one we need to type in a name for the course, and tick the box for Add Course Point Warnings.

Ready to download to the Garmin

Note, if you want to know about the different file formats above then here’s a good link, or you can find loads by googling it.

At this point your Garmin should be connected via USB to your PC or Mac and you would click the gpx line next to To Garmin GPS: This will give you this screen

Clicking on Write Course will transfer the file to your Garmin.  Now, I’m not sure if this is the same on PC as it is on Mac (which I use) so this may not apply to you.  The driver transfers the file to the Garmin as a file called course.gpx.  Which means it appears in my rides list as course.  And then if you try to download another it will try to overwrite it because that will be called course too.  So I have to change the name within the Garmin directory structure.  The Garmin will be shown as a volume in the folder structure on both PC and Mac.  Within the Garmin volume there is a directory called GPX.  Within that you will find all your saved rides – in this case course.gpx.  Rename that to the name of the ride and the job is done.

Finally you need to change a setting in your Garmin.

If you use the instructions above to follow rides mapped on a computer it is really important that you turn off Automatic recalculation of route.  There is a level of inaccuracy in the route planning software and within the Garmin GPS software so from time to time the 705 will suggest you are off route even when you aren’t.  Automatic recalculation will then try to find the shortest distance to the end – which is not likely to be the route you wanted.  So I set this to Prompted.  That way it let’s me know if it thinks I’m off route, but I get to choose whether it recalculates or not.  To do this click the Menu button, then Settings, then Routing and you will see the screen above.

I recommend this site for lots and lots of general info on Garmin products – well worth a read if you own a Garmin GPS product of any type


Sunday ride – 50 miles and the importance of nutrition

Today I discovered what happens when you get the nutrition side of cycling horribly wrong.  I needed to get back by a certain time to go to the match and so I set my alarm very early for a Sunday morning.  In fact I couldn’t face getting up any earlier so I basically got up, forced an energy bar down and then set off.  Within 5 miles I knew I was in trouble.  My legs felt heavy and I wasn’t up for it at all.  I’d planned my ride to go up to Rossendale, taking a right up to Bacup and then over the hill down to Todmorden and through Hebden Bridge.  Then a right up through Crag Vale to the White House on the peak at Littleborough and down via Hollingworth Lake, Rochdale, Heywood and home.

The route I’d planned contained two big climbs.  Not particularly steep but long.  The first would start at about 500ft and climb up to over 1250ft over a period of 6 miles.  The second would be virtually 1000 ft of climbing over 5.5 miles.  So I’m not even at the first climb and feeling bad, and thinking about seriously shortening the ride.  At that moment I was thinking about the issues I would face on the actual ride itself and I figured that I needed to keep going simply to put more “miles in the bank”.  Every bit of training I do now will, in the long run, be beneficial.  I got to Bacup and started up the long climb.  I was onto the small ring at the front pretty much straight away as I ground my way up the hill.  Surprisingly, as I got towards the top I started to feel better, and at the summit itself I stopped and had a celebratory energy gel before I launched myself down the well-earned descent.

Oh, and my Garmin is behaving itself again. Weird!

Cutting through Todmorden and Hebden Bridge and I turned right  to start the next ascent.  By now I was starting to feel much better and I made it most of the way up on the big ring at the front.  On the way up near the summit I stopped to look back over my shoulder and take this snap

The only way is up

The route took my past the Blackstone Edge reservoir and then right to the White House at Littleborough.  Whether the gels and energy bars had kicked in at this point I don’t know, but I was feeling strong again, like I had a second wind.

White House, Littleborough

This is the start of a great descent – the first 1.5 miles of which I averaged over 30mph!  I then skirted round the edge of Hollingworth Lake and headed back through Rochdale.

Hollingworth Lake

At this point I realised that my slow start was in danger of making me late, so I had to really push hard to get home in time, averaging 17mph over the last 10 miles.  Considering the way I’d been felling I was more than happy with that.

Total distance was 50.5 miles in 3hrs 34mins at an average of 14.2mph.  2600ft of climbing meant I used 2734 kcals

Very happy with this weekend, clocking up over 156 miles.  I’m not sure I’m going to hit my training target of 2000 miles (excluding my commuting miles) but I’ll give it a very good go!