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Discussion Starter · #1 ·
When you set up your Garmin Edge what do you put in for your weight. Do you put your weight or the combined weight of yourself gear and bike? (There is just one input filed for weight.)

I originally put in just my weight. The various data measurements on a given ride recorded simultaneously with both the Edge and my Strava iPhone application are pretty spot on in comparison for the same ride as far as speed, distance, and time calculations. But the estimated power data is on average about 25 percent lower than the Strava data.

I wonder if the distance is due to weight in that Strava includes both your weight and the weight of your bike combined. The Edge on the other hand just has one field or entry for "your weight" which when I set it up was just my weight and not the combined weight of my bike. I'm figuring that if I go in and change the weight on the Edge to reflect the combined weight of myself and the bike the estimated watts on the Edge should be very close like the other measurements to Strava's.

No I'm not interested in or care about the benefits of or using a power meter. I'm just interested in the issue above. So any input on your experience for what I seek would be appreciated. Thanks! :)
 

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estimated power is kinda garbage on strava... especially if you are use GPS for speed. You can put what ever you want sometimes it might be ok..sometimes not, in other words "it depends"

you may not be interested in the benefits of using a PM, but that is the big one :D
 

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estimated power is kinda garbage on strava... especially if you are use GPS for speed. You can put what ever you want sometimes it might be ok..sometimes not, in other words "it depends"

you may not be interested in the benefits of using a PM, but that is the big one :D
"Estimated power" is always garbage....whether it is Strava or what have you. Made up number to make you feel better. GPS for speed a very accurate BTW, so long as you maintain a consistent speed. It is more accurate than your car speedo. It gets probelmatic the less consistent speed is, however.


Either way, you want power data that actually means something....get a power meter, otherwise all those imaginary numbers are just there to make you feel good and go "wow"
 

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Unfortunately, there's no real answer.... its all just guesses anyway. You're expecting consistent results from a testing scenario that uses completely inconsistent variables. Try changing the weights, perhaps they'll match up better, if it doesn't, its not like there will be any harm.
 

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GPS for speed a very accurate BTW, so long as you maintain a consistent speed. It is more accurate than your car speedo. It gets probelmatic the less consistent speed is, however.
Actually, relying strictly on GPS data is extremely problematic as detailed in this article from bicycling magizine.... As they state in the article, it says something about GPS data when almost every GPS manufacturer on the planet sets their units to use sensor based data to override the GPS data when a sensor is present.

How Your GPS Lies to You | Bicycling
 

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Discussion Starter · #6 ·
I know all about GPS data, power meters, and the algorithim used by Strava.

All I asked and all I'm interested in is does anyone here have a Garmin Edge 1000 (or for that matter any other Edge product) and if so what do you enter in the "Your weight section?" Do you enter just your weight or the combined weight of you and your bike?

Thanks! :)
 

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yes I have a 1000...I enter my weight (not the bike) but I use a power meter because anything is "highly suspect"

your welcome:D
 

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Actually, relying strictly on GPS data is extremely problematic as detailed in this article from bicycling magizine.... As they state in the article, it says something about GPS data when almost every GPS manufacturer on the planet sets their units to use sensor based data to override the GPS data when a sensor is present.

How Your GPS Lies to You | Bicycling
Actually you're not correct about that.

Garmin units specifically...which account for almost all GPS units anyone ever cares about... don't use a speedo sensor to "override" GPS data. They use GPS data to calibrate a rollout measurement, and on device during your ride will prefer that over GPS.... Nice thing about the speedo sensor is that it isn't as prone to drift in position or have the lag issues with GPS calculation (the later requiring some wicked fast on-the-fly special relativity mathematics). Bad thing, the speedo sensor assumes a steady wheel circumference-which if you do a commute ride with 10-20lbs of excess stuff in your bag in the morning/afternoon and then a fun ride in the evening can cause great discrepancy in data presuming you don't alter your tire pressure. Also tires wear and flatten which changes wheel circumference too. Also you run into the problem of who is actually correct about distance and altitude, the atlas and topo maps sites ain't always right. AAMOF, I've found most of the time that online topo data is pretty far off about climbs in Nebraska. Highway markers aren't always accurate either.

BTW Bicycling as is typical of their half-assed writing...forgets to mention that ALL the GPS positional data is still recorded and is inside the *.fit file for your ride whether you ride with a speedo sensor or not. Strava and the like prefer that rather than speedo data. If you ever open a *.fit file in an editor like the excellent Fit File Repair Tool it is completely self evident. Your Edge during your ride will prefer the speedo if you have it and it appears to be working normally (i.e. Edge sees the speedo returning speeds consistent with GPS movement), but Strava and Connect will prefer the GPS coordinate data and then interpolate-averaging against lots of other rides to try and correct.

GPS is still better than a bad rollout measurement...which unless you use a Garmin to do a GPS calibrated rollout, odds are you'll struggle to do better on your own. And most roadies most of the time aren't riding the same worst case scenario as Bicycling writes about-a closed small course of tightly compacted loops with tons of elevation change and barometric pressure changes of 100milibar in one ride.

I know all about GPS data, power meters, and the algorithim used by Strava.
All I asked and all I'm interested in is does anyone here have a Garmin Edge 1000 (or for that matter any other Edge product) and if so what do you enter in the "Your weight section?" Do you enter just your weight or the combined weight of you and your bike?

Thanks! :)
Strava specifically has an entry for your equipment's weight as well as athlete weight. Connect has a field for bikes, but as is typical of the half-unfinished Connect interface leaves out weight.



Either way "virtual power" is an imaginary number to make you feel better whether your weight is plus/minus 15-20lbs doesn't change the fact you're dealing with feel-good numbers that don't have basis in empirical measurement.
 

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Actually, the speed sensor DOES override the GPS data...
If a speed sensor is present, then a Garmin will use that to determine speed, if the battery goes flat, magnet falls off or if you don't have a speed sensor then it will use GPS data.

The Garmin will use two methods to set wheel size, Automatic and Manual.
- with manual you sit on the bike and roll a wheel one whole revolution forward and measure the distance, enter that measurement into the Garmin and every wheel rotation will be that exact measurement.

- with automatic, the Garmin uses some pre determined black magic using GPS and counting wheel revolutions of the magnet and a predetermined distance and then sets the wheel circumference accordingly. It continues to do this and can change throughout the ride although I don't think anyone really knows how or when. It can get thrown out under poor GPS conditions or twisty roads. Some people claim it is accurate, I tried it out just the other day where the automatically measured circumference was 2093mm where a manual rollout and measure was 2125mm.

in both cases above, speed is derived from the speed sensor whilst riding unless it fails and then falls back to plan B which is GPS.

from my experience, using GPS only to derive speed is a bit hit and miss, speed seems to drift around all over the place, enough at least for me to recognise something was wrong with my speed sensor. Perhaps it might be better with my 510 and GPS/GLONAS than what my 500 was.
 

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I forgot to add, in the Garmin 510 (not sure if it's the same on the 1000) you enter your own body weight under your user profile and your bike/equipment weight under the bike profile. Presumably the Garmin will add both values together to determine power.
 

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Discussion Starter · #12 ·
There is no place ON THE GARMIN EDGE 1000 that has a field, (that I'm aware of--the product is new to me) for adding a bike weight. A point that I made abundantly clear over and over in several posts which was the primary reason for the OP and subsequent post by me. (Guess you missed that part.) They GARMIN do have a field or section for gear where you can choose bike and they ask the make and model but that's it for the bike. As I stated Strava does have the weight for rider and the weight for the bike. Garmin does not. Hence the reasonable explanation for why Garmin is recording significantly lower estimated power than Strava as all the GPS data has on the Strava app pushing a total weight significantly greater than Garmin .

All things equal the lighter weight going the same speed on the same route via Garmin will show less estimated power than the Strava app that showing greater weight moving the same speed over the same route as the Garmin and hence greater estimated speed on the Strava app v Garmin data.

Amazing.
 

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Sorry, but you weren't that clear at all, you did say there was only one field, but did not even mention not being able to find a bike weight etc. Yes, I only have one field under my profile too which is what you said and how I read the OP.

But I agree, it would seem crazy not to be able to set a weight under a bike profile, seems a step badkwards, but in that case would definitely enter a combined weight under user profile. Not sure what you do if you have two bikes though.
 

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Actually, the speed sensor DOES override the GPS data...
If a speed sensor is present, then a Garmin will use that to determine speed, if the battery goes flat, magnet falls off or if you don't have a speed sensor then it will use GPS data.
Only while looking at the data live on the device.

All the analytical softwares/sites commonly in use (AKA Strava and Connect) prefer the GPS data inside each and every *.fit file unless you manually turn the GPS off. And it is those that put out imaginary power numbers.
 

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I've read your OP and understand your questions on the Strava/Garmin power data relative to weight input.

If you think that total weight is the factor then just add the weight of your bike/gear as your body weight.

My question to you is why are you not interested in "real" data for power?

Strava and Garmin are estimates, not reality. Kind of like which is better at picking the winner of the presidential election, psychic or ouija board? Either one can be right or can be wrong but both are a crapshoot.
 

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There is no place ON THE GARMIN EDGE 1000 that has a field, (that I'm aware of--the product is new to me) for adding a bike weight. A point that I made abundantly clear over and over in several posts which was the primary reason for the OP and subsequent post by me. (Guess you missed that part.)
NO.. you did make it abundantly clear.... but for some reason, you're missing the point that all of us are making in that it doesn't really make a lick of difference what you enter.... guesstimated power is just that, a guess. it is NOT accurate. I don't understand why you just don't enter the combined weight as you're suggesting and see if the numbers more closely match. What would be the harm? Its not as if you're going to launch rockets and start WWIII if you do it incorrectly. My guess is, the number may be a little closer to each other, but will still have little to no bearing on actual power numbers.
 

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There is no place ON THE GARMIN EDGE 1000 that has a field, (that I'm aware of--the product is new to me) for adding a bike weight. A point that I made abundantly clear over and over in several posts which was the primary reason for the OP and subsequent post by me. (Guess you missed that part.) They GARMIN do have a field or section for gear where you can choose bike and they ask the make and model but that's it for the bike. As I stated Strava does have the weight for rider and the weight for the bike. Garmin does not. Hence the reasonable explanation for why Garmin is recording significantly lower estimated power than Strava as all the GPS data has on the Strava app pushing a total weight significantly greater than Garmin .

All things equal the lighter weight going the same speed on the same route via Garmin will show less estimated power than the Strava app that showing greater weight moving the same speed over the same route as the Garmin and hence greater estimated speed on the Strava app v Garmin data.

Amazing.
Yeah really, not at all clear why you're concerned about trying to get two **guesses**, that probably use different estimating methods, to agree. If you *really* care about power, get a power meter; there are several reasonably affordable ones out there now - all of which are going to be more accurate than any software guesstimate. Otherwise, I'd just recommend believing the guesstimate (Garmin or Strava) that makes you feel better about yourself.

FWIW, *for me* - and I'm 100% SURE that this only applies to me due to some unique combination of weight, terrain, aerodynamics of me+bike, etc. - the Strava estimates are reasonably (and surprisingly) close to real power data that I've gotten from both Powertap and Stages power meters - at least for non-windy rides. I've never used or looked at the Garmin estimates.
 

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When you set up your Garmin Edge what do you put in for your weight. Do you put your weight or the combined weight of yourself gear and bike? (There is just one input filed for weight.)

I'm figuring that if I go in and change the weight on the Edge to reflect the combined weight of myself and the bike the estimated watts on the Edge should be very close like the other measurements to Strava's.

No I'm not interested in or care about the benefits of or using a power meter. I'm just interested in the issue above. So any input on your experience for what I seek would be appreciated. Thanks! :)


I don’t have a Garmin. But a friend does and I asked him. He says there aren’t separate fields in the user interface for his device to enter separate weights of bike and rider. There is just one data entry field for the weight.

I’ve used Strava since about 2010 or 2011. My last bike was stolen in 2012 and with it all the things attached to it such as my power meter. When I got a new bike I didn’t add a power meter to it. Save the money for other things.

I find the estimated power figures for the Strava estimate power expressed in watts as well as all the info via my Smartphone app functionally useful. It’s socially utilized too with other riders, a combination of friends and strangers that ride where I do.

It’s true that a power meter gives a person more accurate information as to the true power in watts they generate than the estimated wattage given by software apps. (Maybe that’s why they call it “estimated?”) That being said only a two-dimensional thinking booger-eating moron would claim that the estimated power figures could not be positively utilized in a variety of ways.

One cannot help but be appalled at the mentally irregular rude obnoxious content of some of the responses to your question in your thread starting post. What part of your original post where you explicitly state that you don’t want to hear about power meters do they not understand? Those particular individuals that read it and act like they “don’t understand” actually really do. Some of them post in response just for their need to make everything about themselves and hence the histrionic or ego driven rudeness while ignoring your question or deliberately failing to try and assist you with what you asked. Their ilk infects all the posting forums in social media. They diminish the positive posts made and actually dissuade or drive off others that would otherwise posts in a cordial constructive and responsive manner.
 

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The ops last paragraph is cheeky.. So he deserves to get whatever he gets .. IMHO.

I think I tried to stay nice .. ?
 

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I don’t have a Garmin. But a friend does and I asked him. He says there aren’t separate fields in the user interface for his device to enter separate weights of bike and rider. There is just one data entry field for the weight.

I’ve used Strava since about 2010 or 2011. My last bike was stolen in 2012 and with it all the things attached to it such as my power meter. When I got a new bike I didn’t add a power meter to it. Save the money for other things.

I find the estimated power figures for the Strava estimate power expressed in watts as well as all the info via my Smartphone app functionally useful. It’s socially utilized too with other riders, a combination of friends and strangers that ride where I do.

It’s true that a power meter gives a person more accurate information as to the true power in watts they generate than the estimated wattage given by software apps. (Maybe that’s why they call it “estimated?”) That being said only a two-dimensional thinking booger-eating moron would claim that the estimated power figures could not be positively utilized in a variety of ways.

One cannot help but be appalled at the mentally irregular rude obnoxious content of some of the responses to your question in your thread starting post. What part of your original post where you explicitly state that you don’t want to hear about power meters do they not understand? Those particular individuals that read it and act like they “don’t understand” actually really do. Some of them post in response just for their need to make everything about themselves and hence the histrionic or ego driven rudeness while ignoring your question or deliberately failing to try and assist you with what you asked. Their ilk infects all the posting forums in social media. They diminish the positive posts made and actually dissuade or drive off others that would otherwise posts in a cordial constructive and responsive manner.
If someone came to you asking about interior decorating and feng shui when their house was about to fall off the cliff it was on, what would you do?
 
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