Last year I bought a Polar S720i and the "Polar Power System". These works fine on my racing bike (1). However, I just bought another bike (2) and installed the wireless Speed sensor on it and used the S720i for this bike too (without the Power System). In this setup I experience abnormal HR readings, e.g., low values like 30-80 (or even 0) while the HR should be > 120. Thereafter I used bike 1 (with Power System and hence wired speed, cadence, power sensors) and the HR shows the right values all the time (no abnormal HR readings). I used the same procedure to put the transmitter on in both cases (moist the electrodes etc; I've read the Polar FAQ about this problem but none of the items seems to apply for this case).
Is there some way to get the correct HR readings also for setup 2? What should I try to solve the problem for bike 2?
"Claus Assmann" <ca+sendmail(no-copies-please)@mine.informatik.uni-kiel.de> wrote in message news:[email hidden]...
Quoted message said:
Last year I bought a Polar S720i and the "Polar Power System". These works fine on my racing bike (1). However, I just bought another bike (2) and installed the wireless Speed sensor on it and used the S720i for this bike too (without the Power System). In this setup I experience abnormal HR readings, e.g., low values like 30-80 (or even 0) while the HR should be > 120. Thereafter I used bike 1 (with Power System and hence wired speed, cadence, power sensors) and the HR shows the right values all the time (no abnormal HR readings). I used the same procedure to put the transmitter on in both cases (moist the electrodes etc; I've read the Polar FAQ about this problem but none of the items seems to apply for this case).
Is there some way to get the correct HR readings also for setup 2? What should I try to solve the problem for bike 2?
The wired / wireless speed/cadence sensors, presence or absence or power sensor shouldn't affect pulse sensing. I assume that you must be using the special handlebar mount on the bike with the power system. Where are you locating the S720i on the other bike without the power system? Does the other bike have anything else electronic on it that might affect pulse sensing?
I'm doing exactly what you are doing with the my Polar S720i on my two bikes without any heart rate sensing problems. My only problem has been keeping the S720i properly seated in the bracket on the bike with the power sensor. This affects only speed/cadence/power and not heart rate sensing.
The wired / wireless speed/cadence sensors, presence or absence or power sensor shouldn't affect pulse sensing. I assume that you must be using the special handlebar mount on the bike with the power system. Where are you locating the S720i on the other bike without the power system? Does the
On the stem (using the default handlebar mount), so it's rotated by 90 degrees (it's easier than mounting it on the handlebar due to the shift/brake cables). Could that be a problem? IMHO it shouldn't as runners wear the receiver on their wrist (right?), so it can be in any angle relative to the transmitter.
Quoted message said:
other bike have anything else electronic on it that might affect pulse sensing?
No, nothing else.
Quoted message said:
I'm doing exactly what you are doing with the my Polar S720i on my two bikes without any heart rate sensing problems. My only problem has been keeping the S720i properly seated in the bracket on the bike with the power sensor.
I ran into that problem a few times at the beginning too.
"Claus Assmann" <ca+sendmail(no-copies-please)@mine.informatik.uni-kiel.de> wrote in message news:[email hidden]...
Quoted message said:
BobT said:
The wired / wireless speed/cadence sensors, presence or absence or power sensor shouldn't affect pulse sensing. I assume that you must be using the special handlebar mount on the bike with the power system. Where are you locating the S720i on the other bike without the power system? Does the
On the stem (using the default handlebar mount), so it's rotated by 90 degrees (it's easier than mounting it on the handlebar due to the shift/brake cables). Could that be a problem? IMHO it shouldn't as runners wear the receiver on their wrist (right?), so it can be in any angle relative to the transmitter.
Quoted message said:
other bike have anything else electronic on it that might affect pulse sensing?
No, nothing else.
Quoted message said:
I'm doing exactly what you are doing with the my Polar S720i on my two bikes without any heart rate sensing problems. My only problem has been keeping the S720i properly seated in the bracket on the bike with the power sensor.
I ran into that problem a few times at the beginning too.
Thanks for your reply!
I don't see why your stem mount would not work. As you suggest, the 90 degree rotation shouldn't matter. You could try different locations temporarily such as your wrist, top of handlerbar etc. to see if this has any effect on the heart rate sensing problem. I'm stumped otherwise. You might try calling polar directly and asking for help.
"Claus Assmann" <ca+sendmail(no-copies-please)@mine.informatik.uni-kiel.de> wrote in message news:[email hidden]...
Quoted message said:
BobT said:
The wired / wireless speed/cadence sensors, presence or absence or power sensor shouldn't affect pulse sensing. I assume that you must be using the special handlebar mount on the bike with the power system. Where are you locating the S720i on the other bike without the power system? Does the
On the stem (using the default handlebar mount), so it's rotated by 90 degrees (it's easier than mounting it on the handlebar due to the shift/brake cables). Could that be a problem? IMHO it shouldn't as runners wear the receiver on their wrist (right?), so it can be in any angle relative to the transmitter.
Quoted message said:
other bike have anything else electronic on it that might affect pulse sensing?
No, nothing else.
Quoted message said:
I'm doing exactly what you are doing with the my Polar S720i on my two bikes without any heart rate sensing problems. My only problem has been keeping the S720i properly seated in the bracket on the bike with the power sensor.
I ran into that problem a few times at the beginning too.
Thanks for your reply!
I don't see why your stem mount would not work. As you suggest, the 90 degree rotation shouldn't matter.
The orientation of the watch definitely has influence on the speed reading. If I put de HRM on my wrist the speed/cadence readings are all messed up. Don't remember if the HR was also messed up.
"Lou Holtman" <[email hidden]> wrote in message news:[email hidden]...
Quoted message said:
The orientation of the watch definitely has influence on the speed reading. If I put de HRM on my wrist the speed/cadence readings are all messed up. Don't remember if the HR was also messed up.
I've had similar experience with the Polar 720i on my bike with the wireless cadence and speed sensors. With the watch on my wrist, if I sit up and take my hand off the bar to look at the watch, I sometimes don't get speed or cadence info. I have assumed that occurs because that move puts the receiver/watch too far away from the wireless transmitters. I think the polar manual says the maximum distance for the cadence transmitter is 80 cm and maximum distance for the speed transmitter is 50 cm. As one would expect, I have not seen problems with heart rate sensing with the receiver on my wrist. This is why I suggested trying the setup with the watch on his wrist or on top of bars just to see, if in his case, watch/receiver position had anything to do with the heart rate sensing problem.
"Lou Holtman" <[email hidden]> wrote in message news:[email hidden]...
Quoted message said:
The orientation of the watch definitely has influence on the speed reading. If I put de HRM on my wrist the speed/cadence readings are all messed up. Don't remember if the HR was also messed up.
I've had similar experience with the Polar 720i on my bike with the wireless cadence and speed sensors. With the watch on my wrist, if I sit up and take my hand off the bar to look at the watch, I sometimes don't get speed or cadence info. I have assumed that occurs because that move puts the receiver/watch too far away from the wireless transmitters.
In my case it also occurs when I just turn my wrist to look at it and not putting the watch further from the sensor.
I think the
Quoted message said:
polar manual says the maximum distance for the cadence transmitter is 80 cm and maximum distance for the speed transmitter is 50 cm. As one would expect, I have not seen problems with heart rate sensing with the receiver on my wrist. This is why I suggested trying the setup with the watch on his wrist or on top of bars just to see, if in his case, watch/receiver position had anything to do with the heart rate sensing problem.
I've had similar experience with the Polar 720i on my bike with the wireless cadence and speed sensors. With the watch on my wrist, if I sit up and take my hand off the bar to look at the watch, I sometimes don't get speed or cadence info. I have assumed that occurs because that move puts the receiver/watch too far away from the wireless transmitters. I think the polar manual says the maximum distance for the cadence transmitter is 80 cm and maximum distance for the speed transmitter is 50 cm.
I find the Polar 720i so erratic that I never trust it as a single instrument. I keep a standard Cateye computer on all my bikes and that way I know I'll have a perfect reading throughout the ride.
You can increase the signal strength emitted from the sensors. Open up the sensor by taking it off the bike and removing two tiny screws you'll find in the fork hollow. Inside you'll find a standard electronic jumper that can connect two of the three prongs. From the factory it is shipped in the standard low-power position. Move the jumper over to get a bit more range (but less battery life) from your sensor and this will improve the situation, but not cure it.
I don't see why your stem mount would not work. As you suggest, the 90 degree rotation shouldn't matter. You could try different locations
It seems it does... Today I simply "tied" the receiver to the handlebar (it was a bit loose, but otherwise ok) and I didn't notice any wrong readings. I hope this wasn't just a coincidence.
