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Discussion Starter · #1 ·
I did do a search, but a lot of the info. I saw was dated back to 2006-2007.

Anyways, in terms of tracking your basic cycling information like mph/avg. speed/ max. speed, distance traveled, temp., altitude, etc., how accurate are the newer GPS-based cyclometers (eg. Garmin edge 500 and the likes)? I know they are pretty good at locating your position, but I'm just talking about the performance measurements. Thanks.
 

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The Garmin 500 works very well. I had the same fears when I bought my 500, and was seriously considering the cadence/speed option. But, it turns out, the GPS is very good and keeps track of location and speed well.
 

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nightfend said:
The Garmin 500 works very well. I had the same fears when I bought my 500, and was seriously considering the cadence/speed option. But, it turns out, the GPS is very good and keeps track of location and speed well.
Agreed. I have the cadence/speed sensor, but it's not on the bike.
 

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I use my 705 with a wheel/crank sensor so the unit knows immediately when I'm moving and also records cadence. I "think" that improves my information but can't tell you how much.
The data I get seems to be consistent with my previous bike computer as far as mileage. And my speed always correlates well with my buddies when we compare.
 

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they're very good

I use a garmin for running, and on race courses it's always very close when comparing recorded distance vs the supposed length of the race

over 7 road marathons, the variation in distance from course to course has been 1/8 miles, that's half a lap around a high school track. the actual error may be even smaller than that as there are a couple other factors as to why you'd see variations in total distance over a race. (shortest clocked at 26.23, longest clocked at 26.38)

1/8 a mile over 26.2
 

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I have been using a non-cycling specific garmin for 6 years now along with SportTracks. It is as accurate as you would need.
 

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I have a 705 as well. It can track data through both the gps and wheel sensor. I believe it tracks elevation through maps and global positioning so that should be very accurate as well. I even use it when running. It's small enough to tuck away in my fuel belt and it's ok to carry by hand. I've tried footpod systems like nike and polar but nothing beats the gps for accurate data.

I believe garmin has a new 8 system as well.
 

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Discussion Starter · #8 ·
Thanks for the feedback. I actually recently purchased a Garmin Edge 500 without the cadence and HR monitor. I took it on a 50 mile ride this past Sunday, and loved it. It was nice to see the speed, altitude, temp., distance, and time all on the same page!

The reason I posted this thread was b/c after purchasing the unit, I started doing some post-purchase research and came across a few threads where cyclists were claiming that GPS-based cyclometers were not that accurate when computing speed/distance/ etc versus the non-gps ones. Hence, I started to wonder how accurate my Garmin 500 was. Great to hear that they are fairly accurate :thumbsup:
 

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Cni2i said:
Thanks for the feedback. I actually recently purchased a Garmin Edge 500 without the cadence and HR monitor. I took it on a 50 mile ride this past Sunday, and loved it. It was nice to see the speed, altitude, temp., distance, and time all on the same page!

The reason I posted this thread was b/c after purchasing the unit, I started doing some post-purchase research and came across a few threads where cyclists were claiming that GPS-based cyclometers were not that accurate when computing speed/distance/ etc versus the non-gps ones. Hence, I started to wonder how accurate my Garmin 500 was. Great to hear that they are fairly accurate :thumbsup:

Mine is coming this week - I will side by side it with my old cateye2 mity......hopefully it is very close.
 

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Cni2i said:
Thanks for the feedback. I actually recently purchased a Garmin Edge 500 without the cadence and HR monitor. I took it on a 50 mile ride this past Sunday, and loved it. It was nice to see the speed, altitude, temp., distance, and time all on the same page!

The reason I posted this thread was b/c after purchasing the unit, I started doing some post-purchase research and came across a few threads where cyclists were claiming that GPS-based cyclometers were not that accurate when computing speed/distance/ etc versus the non-gps ones. Hence, I started to wonder how accurate my Garmin 500 was. Great to hear that they are fairly accurate :thumbsup:
My Edge 500 used to be really accurate on total ascent/descent, but I upgraded the firmware about a month ago and it's not nearly as accurate as it used to be.

For example, on a 25 mile out/back or loop ride with a fair amount of climbing, my ascent and descent used to be within +/- 25 feet of each other. Now I'm seeing as much as 200-300 feet of difference. I want to see zero. :cryin:

If any Edge 500 owners have any suggestions, I'm all ears.
 

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my suggestion on the elevation craziness is when you upload the activity, in the lower left corner there's an "elevation correction" enabled/disabled

if you enable it, it's going to use elevation data based on maps vs elevation determined by GPS signal, much more consistent

cut and pasted from their explanation



What are Elevation Corrections?

Elevation Corrections cross reference the horizontal position (latitude/longitude) provided by the GPS with elevation data that has been acquired by professional surveys. When corrections to elevation data are made, each trackpoint of your activity now contains the elevation from the web service, not the elevation provided by your GPS device.
Garmin Connect selectively applies corrections to depict a more realistic representation of your elevation experience. Activities recorded from devices without a barometric altimeter are enabled with Elevation Corrections by default. Alternatively, activities recorded by devices with a barometric altimeter generally contain accurate elevation data and therefore Elevation Corrections are disabled by default. For those users who are familiar with the MotionBased Gravity service, this is the same service.
 

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I would and have highly recommended SportTracks and a few of their "correction" plugins
 

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Garmin 500

I have the Garmin Edge 500. It seems fairly accurate in speed and distance but it is way off on altitude (+/-400ft) and temperature (+/-10). I did a 30 mile ride the other day at 300 ft. below sea level! Stopped and reset it 3 times but couldn't get it above water. I'm always surprised to find my house has sunk 100 feet when I return home from my rides.

And even though Garmin claims it will support multiple bikes it really doesn't with any useful functionality.

But it is fun to dump to the computer and look at the ride profiles.
 

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nightfend said:
The Garmin 500 works very well. I had the same fears when I bought my 500, and was seriously considering the cadence/speed option. But, it turns out, the GPS is very good and keeps track of location and speed well.
AFAIK, even with the speed sensor the computer uses GPS data to measure speed, and only uses the speed sensor if it loses the GPS signal.
 

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Elevation correction is only correct where there is data. Bridges over streams and rivers, for example, will often show the drop all the way to the water and back up. We have one bridge here that is several hundred feet over the river. If I use the elevation correction, my numbers are totally devoid of any sense.
 

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DrRoebuck said:
AFAIK, even with the speed sensor the computer uses GPS data to measure speed, and only uses the speed sensor if it loses the GPS signal.

It's actually the complete opposite of this. The Edge 500 is most accurate when using the cadence sensor/speed magnet. Garmin actually recommends this in their manuals. If there is no cadence sensor then it will use the GPS which is not as accurate.

I know this because the whole point of me wanting an Edge 500 was to have NO WIRES and NO SENSORS. I asked them the question via email and they recommended the sensor if I desired accuracy.

Luckily I purchased it and have been absolutely thrilled with the heart rate and cadence data. I rarely look at average speed or current speed. It's all about that 100rpm cadence and 150+ bpm heart rate for me to know I'm getting a great workout.

I should put the Edge on my other bike and use only the GPS and see what I get on loops that I have done 1000 times. I do know that my Cateye Strada Wireless and Edge 500 with Cadence Sensor were within 0.2 miles on a 25 mile course but they both used a wheel magnet so that's what I would expect!
 

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Discussion Starter · #17 ·
So, it seems that most here like their Garmin cyclometers, but they're far from perfect...but no cyclometer is. What cadence sensor works with the Garmin Edge 500? And cost? Thanks.
 

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Everything's Bigger in TX
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Accurate on the road, yes.
On the trail (speed/distance) not so much unles you use the magnet.

When on the road you're pretty much in a straight line, so the Garmin trackes spot on.
Go on a trail and with all the twists and turns, if you don't have the wheel magnet and sensor, your measuremens will be off.

Even on the 1 sec read/update on my 705 when you zoom in on a trail it has you cutting corners, thus mileage.

If you have the wheel magnet, you're set.

I use at CatEye and my Garmin.
I also use my Polar instead of my Garmin for HR.
Garmins don't take height into consideration like Polar.

All the garmin knows is that I'm 40 and 270 lbs. The Polar knows I'm 6'6".
Caloric burn on some fat shorter guy different than on a larger athletic guy.

I still love my garmin for tracking where I've ridden, not what I've ridden if that makes sense.

Positive reinforcement for sure and fun to geek to.

I have not set up the Cadence sensor yet, I just got my wheel set. Maybe I'll go do that now.
 
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