Garmin 705 and hill gradients
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The grade listed on road signs should read the maximum grade of the hill, not the average, and I find that the 705 is often within about 1% of those signs.0
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colonel_mustard wrote:The grade listed on road signs should read the maximum grade of the hill, not the average, and I find that the 705 is often within about 1% of those signs.
We should ride next to each other to see if the garmins say the same thing.0 -
redddraggon wrote:a_n_t wrote:You need to switch it on a good half an hour before you ride to let it settle down
In my current flat I can't connect to any satellites, and even when I get outside it's takes bloody ages to connect to any. In North Wales it takes seconds to connect.
therei's your problem then. i stick mine on a window ledge and it fires up eventually.0 -
Ive found the 705 poor on the altimeter and grade some times.
On the commute I arrive and I am at 400 ft, when I set off home I am 200 ft lower. Once I was below sea level. You can see on the graph when I get home it slowly corrects itself on the first 20 mins.
Another time in the Peak district on a steep clime 15+ the garmin said 100% + ( thought the hill was steep)
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jthef wrote:Ive found the 705 poor on the altimeter and grade some times.
On the commute I arrive and I am at 400 ft, when I set off home I am 200 ft lower. Once I was below sea level. You can see on the graph when I get home it slowly corrects itself on the first 20 mins.
Another time in the Peak district on a steep clime 15+ the garmin said 100% + ( thought the hill was steep)
That's not especially the 705 that is at fault. Any altimeter will do this as it works off barometric pressure which changes as the weather does. That is why on some days, you can set off out, come back to the same start point (ie home) 4-5 hours later and find that your house has either sunk of floated into the sky by quite a bit. It's just the air pressure has changed and hence the altitude reading with it. Not even commerical aircraft can get around this. This is why pilots the world over set their altimeters to a standard setting when above a set altititude and then re-adjust to the local pressure as they approach their destination.0 -
jthef wrote:it slowly corrects itself on the first 20 mins.
which is why you should turn it on 20 mins or so before you go out! easy!0 -
GavH wrote:[pilots the world over set their altimeters to a standard setting when above a set altititude
you can now sort of do this with firmware 3.1
set a "home" waypoint and you can select the altitude [ easily found on google earth ]
then if you press start within 30 metres of that waypoint the altitude jumps to your correct setting.0 -
On my edge 305 the grade reading is a bit variable, i do the same hill on the way to work and the grade according to my edge 305 is anything from 9% to 12% going up and 7% to 10% coming down. On my edge 305 to get the elevation starting value right fairly quick, i use this method, my home elevation is 86m, when i turn my edge on it will usually read anything from -150m to +300m depending on the current air pressure, once its accuracy is within 30-40 ft the elevation reading rapidly starts coming up or down towards 86m, what you have to do then is , when it reaches your home elevation press start/stop (timer started) wait a few secs then press start/stop (timer stopped) this should freeze the elevation reading at whatever it was when you first pressed the start/stop button,then press reset to set things back to zero, then go into history and delete the lap this created, if you dont do this,when you download your ride the graph on the pc could be out of scale depending on how far off the starting value was when you first switched on,this method gets the start value within plus or minus 2m on nearly every ride, before i discovered this dodge by accident i used to wait anything from a half to one and a half hours for it to slowly come up or down to within +or- 5m of my start elevation, some days it never did, this works on the 305 so might also work on the 705 if you have trouble with the start elevation value, for all i know it might be just my 305 that does this with the elevation reading?0
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its been sorted in V3.1 !0
