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Garmin Speed sensor



 
 
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  #11  
Old February 11th 21, 06:05 AM posted to rec.bicycles.tech
John B.[_3_]
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Posts: 5,697
Default Garmin Speed sensor

On Thu, 11 Feb 2021 02:02:07 -0000 (UTC), Duane
wrote:

Lou Holtman wrote:
Op woensdag 10 februari 2021 om 21:35:51 UTC+1 schreef Mark cleary:
On Wednesday, February 10, 2021 at 1:31:44 PM UTC-6, wrote:
Op woensdag 10 februari 2021 om 18:40:04 UTC+1 schreef Mark cleary:
I have a Garmin 910xt that I use for the bike of course GPS keeps
track of my speed. I decided to get the rear speed sensor that goes
around the rear hub and should come today. So I realize that indoors
it makes sense but what about using it outdoors with the GPS. My
understanding is the speed sensor will overrule the GPS speed data. My
years of using this it is pretty much dead accurate for distance so
speed should be deadly accurate. I have done many long rides and hit
the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor
figuring I can count my cadence anytime I want. So do any of the group
use a speed sensor when riding outdoors? I guess you can hook it up
with Zwift but I have never used Zwift don't see the benefit as long
as I know my speed on and heart rate on the trainer. I have a cateye
at the moment set up for the back wheel on my trainer bike. I give
this garmin a go. Some how Zwift measures power but I cannot figure
out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest
The GPS distance is OK accurate. The speed based on GPS sucks big time.
It goes from 30 km/hr to 25 km/hr and back and forth within seconds. I
don't know what algorithm Garmin uses but it is crap. My Wahoo does a
better job but not as accurate as a speed sensor. I use always a
separate speed sensor when outside and yes it overrules the GPS speed
which wasn't the case a couple of years ago which I never understood
and I complained about that. Ala Garmin doesn't employ the best software people....

Lou
My speed on the GPS seems to be consistent and track pretty even. I also
live in the flatlands that could be another reason. I have always used a
cateye wireless even with the Garmin 910 on the bike. They are almost
deadly consistent with readings never much apart. In fact I did a wheel
roll out on my bike to input the proper wheel diameter for the cateye,
and the margin of error between the GPS and cateye is like 1%. The
overall speed for a 50 mile ride is either the same or possible .1 mph
difference. That is my reluctance to use the sensor outside. I just
hooked it up in the basement and works fine.
Deacon Mark


That is remarkable. I'm a long term Garmin user: Etrex, Edge305, Edge705,
Edge 810 and a Edge1030 and the speed was always crap. For a long time I
didn't care about the speed during the ride so I didn't even had it as a
data field. But on group rides we agree on a max speed so now I have a
speed data field and a speed sensor. I challenge you about the flatness ;-)

Lou


For me it wasn’t flatness but tree cover. The GPS speed would get pretty
crappy. Wheel sensors are much more accurate.


I think it is a GPS failing, not the instrument. I have an altitude
application that apparently accesses GPS to find out where it is and
then refers that to a topography chart in some manner to read
altitude. Sitting still, in one place, the altitude will vary with
almost every reading. Obviously the altitude isn't changing which
leaves the GPS as the only fault. I read that the top quality
professional GPS receivers will plot to within 7 inches of a true
location but will a "made for the masses" device like a hand phone or
a bicycle meter do as well?
--
Cheers,

John B.

Ads
  #12  
Old February 11th 21, 12:50 PM posted to rec.bicycles.tech
Rolf Mantel[_2_]
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Posts: 267
Default Garmin Speed sensor

Am 11.02.2021 um 06:05 schrieb John B.:
I read that the top quality
professional GPS receivers will plot to within 7 inches of a true
location but will a "made for the masses" device like a hand phone or
a bicycle meter do as well?


This kind of accuracy is only possible via "differential GPS", not from
the standard GPS algorithm.
  #13  
Old February 11th 21, 04:53 PM posted to rec.bicycles.tech
Tom Kunich[_4_]
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Posts: 2,196
Default Garmin Speed sensor

On Wednesday, February 10, 2021 at 9:40:04 AM UTC-8, Mark cleary wrote:
I have a Garmin 910xt that I use for the bike of course GPS keeps track of my speed. I decided to get the rear speed sensor that goes around the rear hub and should come today. So I realize that indoors it makes sense but what about using it outdoors with the GPS. My understanding is the speed sensor will overrule the GPS speed data. My years of using this it is pretty much dead accurate for distance so speed should be deadly accurate. I have done many long rides and hit the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor figuring I can count my cadence anytime I want. So do any of the group use a speed sensor when riding outdoors? I guess you can hook it up with Zwift but I have never used Zwift don't see the benefit as long as I know my speed on and heart rate on the trainer. I have a cateye at the moment set up for the back wheel on my trainer bike. I give this garmin a go. Some how Zwift measures power but I cannot figure out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest

There are two reasons that the speed sensor over-rides speed and distance. Because GPS is REALLY crappy at measuring speed and distance in a climb. So the speed sensor and the distance measure of your input of a wheelsize corrects for that.

One thing to be really careful of is that the wheel sensor is attached by a rubber band and it has to be tight enough not to slip especially over rough roads. This can be a problem on small diameter hubs.
  #14  
Old February 11th 21, 08:24 PM posted to rec.bicycles.tech
Mark cleary
external usenet poster
 
Posts: 51
Default Garmin Speed sensor

On Thursday, February 11, 2021 at 9:53:17 AM UTC-6, wrote:
On Wednesday, February 10, 2021 at 9:40:04 AM UTC-8, Mark cleary wrote:
I have a Garmin 910xt that I use for the bike of course GPS keeps track of my speed. I decided to get the rear speed sensor that goes around the rear hub and should come today. So I realize that indoors it makes sense but what about using it outdoors with the GPS. My understanding is the speed sensor will overrule the GPS speed data. My years of using this it is pretty much dead accurate for distance so speed should be deadly accurate. I have done many long rides and hit the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor figuring I can count my cadence anytime I want. So do any of the group use a speed sensor when riding outdoors? I guess you can hook it up with Zwift but I have never used Zwift don't see the benefit as long as I know my speed on and heart rate on the trainer. I have a cateye at the moment set up for the back wheel on my trainer bike. I give this garmin a go. Some how Zwift measures power but I cannot figure out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest

There are two reasons that the speed sensor over-rides speed and distance.. Because GPS is REALLY crappy at measuring speed and distance in a climb. So the speed sensor and the distance measure of your input of a wheelsize corrects for that.

One thing to be really careful of is that the wheel sensor is attached by a rubber band and it has to be tight enough not to slip especially over rough roads. This can be a problem on small diameter hubs.



I used the puppy for the first time this morning on the indoor trainer. Worked great gave me my speed matched the speed of my cateye so now I can take that off less clutter. The cool thing was cadence in that in all these years of cycling I never used one since I can count if I want to know, and speed is the real measure. But given the weather here no chance to ride outside looking at my cadence was distracting...... a good thing. Today for a 15 mile ride I went 15 miles in 47 minutes average cadence was 85, pretty much what I thought it is most of the time. It also confirmed for me that cadence about 100 is pretty hard to sustain for lengths of time like 5-10 miles for sure. A cadence of 110 is wild and probably about the limit of smooth pedaling. Seems I like a bit of resistance and the sweet spot is probably 82-88. The data is consistent as my heart rate for this ride typical of what it usually is. In the end it is probably just another toy distraction that can be good in the basement.

Deacon Mark
  #15  
Old February 11th 21, 09:22 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 163
Default Garmin Speed sensor

On Wednesday, February 10, 2021 at 12:40:04 PM UTC-5, Mark cleary wrote:
I have a Garmin 910xt that I use for the bike of course GPS keeps track of my speed. I decided to get the rear speed sensor that goes around the rear hub and should come today. So I realize that indoors it makes sense but what about using it outdoors with the GPS. My understanding is the speed sensor will overrule the GPS speed data. My years of using this it is pretty much dead accurate for distance so speed should be deadly accurate. I have done many long rides and hit the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor figuring I can count my cadence anytime I want. So do any of the group use a speed sensor when riding outdoors? I guess you can hook it up with Zwift but I have never used Zwift don't see the benefit as long as I know my speed on and heart rate on the trainer. I have a cateye at the moment set up for the back wheel on my trainer bike. I give this garmin a go. Some how Zwift measures power but I cannot figure out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest


If you have a lot of tree cover, or you ride off road a lot, wheel sensors are much more accurate. In fact, there was another forum I was on, where the title of the thread was "Strava: Because corners don't matter". The sampling rate of the particular GPS unit can result in a lot of cut-off corners on winding technical single-track, resulting in a lower average speed and shorter distance. So, yes, I rely mostly on the wheel speed sensor for road and off-road, and base my training on that head unit. I have a Suunto AMBIT3 which loads the GPS data, and use that for strava, because "if it ain't on strava, it didn't happen", and of course there are the oh-so-valuable KOM segments.

I've also used a cadence monitor on every bike I've ridden since 1985. I personally find it very valuable, but not everyone does. I have correlation between speed, cadence, and heart rate. If things aren't lining up properly with my rate of perceived effort (RPE), I know something is off (fatigue level, ambient conditions, etc).. Generally speaking though, even the most die-hard cadence watchers know it's an indicator and a training metric, not anything to really worry about if it seems off. Andrew Coggin (the Power Guru) even went so far at one point to call it a red herring, but he's changed his tune in recent years on the understanding that cadence targets can add one more data point to accurate physiological assessments. However, understanding your optimal cadence for the best bio-mechanical efficiency is very valuable for reaching optimal power output. Hunter Allen - Andrew Coggins research partner - writes extensively about training with cadence, power, and HR, and trains professional bike racers to work towards that sweet spot during hard competitive efforts. There is a lot to be said for cadence drills if you're a racer, and obviously a cadence monitor is necessary for that..

FWIW - I race quasi-cannabal: I cover the head unit so I'm not distracted but the data. If I can keep up or go on an attack, I do. If not, I don't. That's racing. No amount of data is going to help you go any faster when the race has gone up the road.
  #16  
Old February 11th 21, 11:27 PM posted to rec.bicycles.tech
Mark cleary
external usenet poster
 
Posts: 51
Default Garmin Speed sensor

On Thursday, February 11, 2021 at 2:22:16 PM UTC-6, wrote:
On Wednesday, February 10, 2021 at 12:40:04 PM UTC-5, Mark cleary wrote:
I have a Garmin 910xt that I use for the bike of course GPS keeps track of my speed. I decided to get the rear speed sensor that goes around the rear hub and should come today. So I realize that indoors it makes sense but what about using it outdoors with the GPS. My understanding is the speed sensor will overrule the GPS speed data. My years of using this it is pretty much dead accurate for distance so speed should be deadly accurate. I have done many long rides and hit the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor figuring I can count my cadence anytime I want. So do any of the group use a speed sensor when riding outdoors? I guess you can hook it up with Zwift but I have never used Zwift don't see the benefit as long as I know my speed on and heart rate on the trainer. I have a cateye at the moment set up for the back wheel on my trainer bike. I give this garmin a go. Some how Zwift measures power but I cannot figure out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest

If you have a lot of tree cover, or you ride off road a lot, wheel sensors are much more accurate. In fact, there was another forum I was on, where the title of the thread was "Strava: Because corners don't matter". The sampling rate of the particular GPS unit can result in a lot of cut-off corners on winding technical single-track, resulting in a lower average speed and shorter distance. So, yes, I rely mostly on the wheel speed sensor for road and off-road, and base my training on that head unit. I have a Suunto AMBIT3 which loads the GPS data, and use that for strava, because "if it ain't on strava, it didn't happen", and of course there are the oh-so-valuable KOM segments.

I've also used a cadence monitor on every bike I've ridden since 1985. I personally find it very valuable, but not everyone does. I have correlation between speed, cadence, and heart rate. If things aren't lining up properly with my rate of perceived effort (RPE), I know something is off (fatigue level, ambient conditions, etc).. Generally speaking though, even the most die-hard cadence watchers know it's an indicator and a training metric, not anything to really worry about if it seems off. Andrew Coggin (the Power Guru) even went so far at one point to call it a red herring, but he's changed his tune in recent years on the understanding that cadence targets can add one more data point to accurate physiological assessments. However, understanding your optimal cadence for the best bio-mechanical efficiency is very valuable for reaching optimal power output. Hunter Allen - Andrew Coggins research partner - writes extensively about training with cadence, power, and HR, and trains professional bike racers to work towards that sweet spot during hard competitive efforts. There is a lot to be said for cadence drills if you're a racer, and obviously a cadence monitor is necessary for that.

FWIW - I race quasi-cannabal: I cover the head unit so I'm not distracted but the data. If I can keep up or go on an attack, I do. If not, I don't. That's racing. No amount of data is going to help you go any faster when the race has gone up the road.


If I run on a 400 meter track the Garmin will always show I went more distance and faster. Generally if I run 10000 meters on the track it will show I can maybe 6.5 miles instead of 6.2. in straight or nearly straight paths it is deadly accurate. I do may out and back type rides coming back same way and they are never off much at all. I don't remember exactly but less than 2%. It just does not like those 400 meter ovals
Deacon mark
  #17  
Old February 11th 21, 11:44 PM posted to rec.bicycles.tech
Sir Ridesalot
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Posts: 5,270
Default Garmin Speed sensor

On Thursday, February 11, 2021 at 5:27:24 p.m. UTC-5, Mark cleary wrote:
On Thursday, February 11, 2021 at 2:22:16 PM UTC-6, wrote:
On Wednesday, February 10, 2021 at 12:40:04 PM UTC-5, Mark cleary wrote:
I have a Garmin 910xt that I use for the bike of course GPS keeps track of my speed. I decided to get the rear speed sensor that goes around the rear hub and should come today. So I realize that indoors it makes sense but what about using it outdoors with the GPS. My understanding is the speed sensor will overrule the GPS speed data. My years of using this it is pretty much dead accurate for distance so speed should be deadly accurate. I have done many long rides and hit the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor figuring I can count my cadence anytime I want. So do any of the group use a speed sensor when riding outdoors? I guess you can hook it up with Zwift but I have never used Zwift don't see the benefit as long as I know my speed on and heart rate on the trainer. I have a cateye at the moment set up for the back wheel on my trainer bike. I give this garmin a go. Some how Zwift measures power but I cannot figure out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest

If you have a lot of tree cover, or you ride off road a lot, wheel sensors are much more accurate. In fact, there was another forum I was on, where the title of the thread was "Strava: Because corners don't matter". The sampling rate of the particular GPS unit can result in a lot of cut-off corners on winding technical single-track, resulting in a lower average speed and shorter distance. So, yes, I rely mostly on the wheel speed sensor for road and off-road, and base my training on that head unit. I have a Suunto AMBIT3 which loads the GPS data, and use that for strava, because "if it ain't on strava, it didn't happen", and of course there are the oh-so-valuable KOM segments.

I've also used a cadence monitor on every bike I've ridden since 1985. I personally find it very valuable, but not everyone does. I have correlation between speed, cadence, and heart rate. If things aren't lining up properly with my rate of perceived effort (RPE), I know something is off (fatigue level, ambient conditions, etc).. Generally speaking though, even the most die-hard cadence watchers know it's an indicator and a training metric, not anything to really worry about if it seems off. Andrew Coggin (the Power Guru) even went so far at one point to call it a red herring, but he's changed his tune in recent years on the understanding that cadence targets can add one more data point to accurate physiological assessments. However, understanding your optimal cadence for the best bio-mechanical efficiency is very valuable for reaching optimal power output. Hunter Allen - Andrew Coggins research partner - writes extensively about training with cadence, power, and HR, and trains professional bike racers to work towards that sweet spot during hard competitive efforts. There is a lot to be said for cadence drills if you're a racer, and obviously a cadence monitor is necessary for that.

FWIW - I race quasi-cannabal: I cover the head unit so I'm not distracted but the data. If I can keep up or go on an attack, I do. If not, I don't.. That's racing. No amount of data is going to help you go any faster when the race has gone up the road.

If I run on a 400 meter track the Garmin will always show I went more distance and faster. Generally if I run 10000 meters on the track it will show I can maybe 6.5 miles instead of 6.2. in straight or nearly straight paths it is deadly accurate. I do may out and back type rides coming back same way and they are never off much at all. I don't remember exactly but less than 2%. It just does not like those 400 meter ovals
Deacon mark


I liked my Cateye wired computers for touring in Northern Ontario, Canada. I could load my bike then do a roll out measurement and input that into the computer for 99.9% accuracy. When using those computers and topographical maps it's quite easy to locate position or items such as nearly hidden old roads that are barely visible for the road I'm riding on.

It was also very nice to know almost exactly where I was in my trip.

Cheers
  #18  
Old February 11th 21, 11:55 PM posted to rec.bicycles.tech
Tom Kunich[_4_]
external usenet poster
 
Posts: 2,196
Default Garmin Speed sensor

On Thursday, February 11, 2021 at 11:24:37 AM UTC-8, Mark cleary wrote:
On Thursday, February 11, 2021 at 9:53:17 AM UTC-6, wrote:
On Wednesday, February 10, 2021 at 9:40:04 AM UTC-8, Mark cleary wrote:
I have a Garmin 910xt that I use for the bike of course GPS keeps track of my speed. I decided to get the rear speed sensor that goes around the rear hub and should come today. So I realize that indoors it makes sense but what about using it outdoors with the GPS. My understanding is the speed sensor will overrule the GPS speed data. My years of using this it is pretty much dead accurate for distance so speed should be deadly accurate. I have done many long rides and hit the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor figuring I can count my cadence anytime I want. So do any of the group use a speed sensor when riding outdoors? I guess you can hook it up with Zwift but I have never used Zwift don't see the benefit as long as I know my speed on and heart rate on the trainer. I have a cateye at the moment set up for the back wheel on my trainer bike. I give this garmin a go. Some how Zwift measures power but I cannot figure out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest

There are two reasons that the speed sensor over-rides speed and distance. Because GPS is REALLY crappy at measuring speed and distance in a climb.. So the speed sensor and the distance measure of your input of a wheelsize corrects for that.

One thing to be really careful of is that the wheel sensor is attached by a rubber band and it has to be tight enough not to slip especially over rough roads. This can be a problem on small diameter hubs.

I used the puppy for the first time this morning on the indoor trainer. Worked great gave me my speed matched the speed of my cateye so now I can take that off less clutter. The cool thing was cadence in that in all these years of cycling I never used one since I can count if I want to know, and speed is the real measure. But given the weather here no chance to ride outside looking at my cadence was distracting...... a good thing. Today for a 15 mile ride I went 15 miles in 47 minutes average cadence was 85, pretty much what I thought it is most of the time. It also confirmed for me that cadence about 100 is pretty hard to sustain for lengths of time like 5-10 miles for sure. A cadence of 110 is wild and probably about the limit of smooth pedaling. Seems I like a bit of resistance and the sweet spot is probably 82-88. The data is consistent as my heart rate for this ride typical of what it usually is. In the end it is probably just another toy distraction that can be good in the basement.


The way that the pros make spinning easier is to use shorter cranks. I tried it and it actually works and I couldn't tell any difference in climbing speed at ultra-low cadence.
  #19  
Old February 12th 21, 01:58 AM posted to rec.bicycles.tech
John B.[_3_]
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Posts: 5,697
Default Garmin Speed sensor

On Thu, 11 Feb 2021 11:24:34 -0800 (PST), Mark cleary
wrote:

On Thursday, February 11, 2021 at 9:53:17 AM UTC-6, wrote:
On Wednesday, February 10, 2021 at 9:40:04 AM UTC-8, Mark cleary wrote:
I have a Garmin 910xt that I use for the bike of course GPS keeps track of my speed. I decided to get the rear speed sensor that goes around the rear hub and should come today. So I realize that indoors it makes sense but what about using it outdoors with the GPS. My understanding is the speed sensor will overrule the GPS speed data. My years of using this it is pretty much dead accurate for distance so speed should be deadly accurate. I have done many long rides and hit the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor figuring I can count my cadence anytime I want. So do any of the group use a speed sensor when riding outdoors? I guess you can hook it up with Zwift but I have never used Zwift don't see the benefit as long as I know my speed on and heart rate on the trainer. I have a cateye at the moment set up for the back wheel on my trainer bike. I give this garmin a go. Some how Zwift measures power but I cannot figure out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest

There are two reasons that the speed sensor over-rides speed and distance. Because GPS is REALLY crappy at measuring speed and distance in a climb. So the speed sensor and the distance measure of your input of a wheelsize corrects for that.

One thing to be really careful of is that the wheel sensor is attached by a rubber band and it has to be tight enough not to slip especially over rough roads. This can be a problem on small diameter hubs.



I used the puppy for the first time this morning on the indoor trainer. Worked great gave me my speed matched the speed of my cateye so now I can take that off less clutter. The cool thing was cadence in that in all these years of cycling I never used one since I can count if I want to know, and speed is the real measure. But given the weather here no chance to ride outside looking at my cadence was distracting...... a good thing. Today for a 15 mile ride I went 15 miles in 47 minutes average cadence was 85, pretty much what I thought it is most of the time. It also confirmed for me that cadence about 100 is pretty hard to sustain for lengths of time like 5-10 miles for sure. A cadence of 110 is wild and probably about the limit of smooth pedaling. Seems I like a bit of resistance and the sweet spot is probably 82-88. The data is consistent as my heart rate for this ride typical of what it usually is. In the end it is probably just another toy distraction that can be good in the
basement.

Deacon Mark


I would argue just a bit about cadence. Power is essentially torque
versus RPM so to get more power you could either apply more force to
the pedal or simply spin faster with the same pressure so cadence is
important.
--
Cheers,

John B.

  #20  
Old February 12th 21, 03:08 AM posted to rec.bicycles.tech
John B.[_3_]
external usenet poster
 
Posts: 5,697
Default Garmin Speed sensor

On Thu, 11 Feb 2021 14:27:22 -0800 (PST), Mark cleary
wrote:

On Thursday, February 11, 2021 at 2:22:16 PM UTC-6, wrote:
On Wednesday, February 10, 2021 at 12:40:04 PM UTC-5, Mark cleary wrote:
I have a Garmin 910xt that I use for the bike of course GPS keeps track of my speed. I decided to get the rear speed sensor that goes around the rear hub and should come today. So I realize that indoors it makes sense but what about using it outdoors with the GPS. My understanding is the speed sensor will overrule the GPS speed data. My years of using this it is pretty much dead accurate for distance so speed should be deadly accurate. I have done many long rides and hit the same mileage marks almost within 10-50 feet for 20-40 miles.

I also bought the cadence sensor and have never used a cadence sensor figuring I can count my cadence anytime I want. So do any of the group use a speed sensor when riding outdoors? I guess you can hook it up with Zwift but I have never used Zwift don't see the benefit as long as I know my speed on and heart rate on the trainer. I have a cateye at the moment set up for the back wheel on my trainer bike. I give this garmin a go. Some how Zwift measures power but I cannot figure out how that could be anything more than an educated guess.
Deacon Mark............in the very cold midwest

If you have a lot of tree cover, or you ride off road a lot, wheel sensors are much more accurate. In fact, there was another forum I was on, where the title of the thread was "Strava: Because corners don't matter". The sampling rate of the particular GPS unit can result in a lot of cut-off corners on winding technical single-track, resulting in a lower average speed and shorter distance. So, yes, I rely mostly on the wheel speed sensor for road and off-road, and base my training on that head unit. I have a Suunto AMBIT3 which loads the GPS data, and use that for strava, because "if it ain't on strava, it didn't happen", and of course there are the oh-so-valuable KOM segments.

I've also used a cadence monitor on every bike I've ridden since 1985. I personally find it very valuable, but not everyone does. I have correlation between speed, cadence, and heart rate. If things aren't lining up properly with my rate of perceived effort (RPE), I know something is off (fatigue level, ambient conditions, etc).. Generally speaking though, even the most die-hard cadence watchers know it's an indicator and a training metric, not anything to really worry about if it seems off. Andrew Coggin (the Power Guru) even went so far at one point to call it a red herring, but he's changed his tune in recent years on the understanding that cadence targets can add one more data point to accurate physiological assessments. However, understanding your optimal cadence for the best bio-mechanical efficiency is very valuable for reaching optimal power output. Hunter Allen - Andrew Coggins research partner - writes extensively about training with cadence, power, and HR, and trains

professional bike racers to work towards that sweet spot during hard competitive efforts. There is a lot to be said for cadence drills if you're a racer, and obviously a cadence monitor is necessary for that.

FWIW - I race quasi-cannabal: I cover the head unit so I'm not distracted but the data. If I can keep up or go on an attack, I do. If not, I don't. That's racing. No amount of data is going to help you go any faster when the race has gone up the road.


If I run on a 400 meter track the Garmin will always show I went more distance and faster. Generally if I run 10000 meters on the track it will show I can maybe 6.5 miles instead of 6.2. in straight or nearly straight paths it is deadly accurate. I do may out and back type rides coming back same way and they are never off much at all. I don't remember exactly but less than 2%. It just does not like those 400 meter ovals
Deacon mark


But where, on the track are you running? I believe that the official
measurement of a 400 meter track is made 0.3 meters from the inside
curb so if you deviate from that "line" you won't be running 400
meters :-)
--
Cheers,

John B.

 




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