Major navigation issues with Garmin 1030 and 820 devices

Yep I had tried that, reduced the distance a bit, but still didn't select the most obvious and direct route which also is using surfaced roads. Thanks anyway

I’m not I sure I would ever trust a cycling device to determine a route, excepting maybe a return to start using the recorded track.  Part of the issue is how does the device know what might be decent roads to cycle ?.  The device can generate a route based on Popularity Routing, where the device makes a connection to the Connect online via the mobile app and determines if other Garmin users have ridden a particular route.  But these are not auto navigating devices and I don’t think they’re as smart.  I know that in the US, Garmin used to use a company called NavTeq or some such, to develop routing for their auto devices.  Thus somebody was field checking and generating the best method to get from NYC to Boston, as example.  I doubt that outside of Popularity Routing there’s any such think happing with a cycling device.  

Typically I only ride navigable courses or routes I developed in either Garmin Connect or RWGPS and sent to the device.  I might do some searching on Google maps satellite goes to determine if a route looks OK.  I’ve also never had issues with RWGPS not allowing particular roads to be used to generate a route, excepting a road I’m trying to bike on that’s one-way against my direction of travel.  

I've tried & tried with Garmin on this & keep coming up against a brick wall.

As you correctly said the built in Garmin maps don't allow routing by motorised transport and the Road Cycling routing is so restrictive that it omits many perfectly navigable roads by default, without even having these roads available to select in the avoidance settings. This results in the most complex of routes for the shortest of journeys just the avoid anything that might resemble a major road. As an example; my commute in a pretty rural area is about 10 Km. If I try to use the Garmin for the same journey it gives me a 27Km route. 

I've taken to using 3rd party maps now. The downside to using Automobile Routing is the turn guidance popups assumes you are travelling much quicker, so appear way before a turn and usually over a Km beforehand. So for day to day use & when navigating a downloaded course I'll leave it on Road Cycling routing & when I need to navigate on the fly to a point selected on the Garmin I'll use Automobile routing to give a more sensible route

I believe the UK A roads are treated as motorways and assumed to not allow cycling

This assumption is reasonable in the US.

It's a data problem. 

When this sort of thing happen there is often  a restriction in the OSM map data. The road might be tagged as private, prohibited for bikes. Maybe a gate. If you are familiar with OSM you may comb the route you think should be selected and check the ways and tags to see if anything is wrong. Maps do have errors in them. 

my new 830 is clueless, takes me on worst (busy) roads that all cyclists avoid. The popular course with round trip is truly dangerous - i was thinking of selling and buying a 1030. But if problem is with maps or GC then i'm guessing that's not gonna make me happy  

Do you mean the OSM source maps have this restriction or has Garmin dictated this? 

I have an A road, which must be used to get to my house & the Garmin routing will use it eventually. The bizarre thing is why it won't use the road for more of the journey taking convoluted routes to avoid it until it has no other option. If A roads were designated as non cycling I would expect the Garmin to tell me that no routes were available due to not being able to use the road 

If its a Garmin restriction, with driving rules differing across geographic regions a device designed for global use should be able to account for this. It's not a device designed just for the US market . Or is it . All they need to do is add some options in the avoidance settings to permit the use of certain road classifications for Road Cycling if cycling on them is permissable.

This isn't just a UK issue. Although I haven't tried it in the US I've had issues in all the European countries I've been to. 

When using the free OSM maps the distance and route selected appears to be correct. In my opinion there is a massive issue with the Garmin maps which make them useless "out of the box" for navigating to a specific location. Following a downloaded route appears fine using the Garmin maps, you just have a major issue when you deviate from it.

harris165 , can you please write down Star- and Endpoint so that we are able to look what happens?