Polar Speed Sensor 2 mounting locations and performance

I have at least one each of the speed sensors from pre "S-series" and
first and second generation S-series. I started to use the latest
version of the speed sensor sold as the "S-series Speed Sensor 2"
mounted on the right fork blade. When I used a 710 (about 2001 model)
with a first generation S-series speed sensor (the first one molded
that mounts flush against the fork blade) I would get spikes in the
reported speed that would be corrected with the PPP error correction
tool. I would normally see an average of 2 to 3 spikes per hour of road
time. With the 720 and a Speed Sensor 2 I get almost no spikes. I also
noticed that I can wear the watch on my wrist and still get both the
speed and cadence to function.

It got me wondering if anyone has tried this latest sensor on the rear
wheel? I know that the signal is very directional and I recall that at
least one version had a 3 position DIP switch to control the signal
strength. Any feedback would be appreciated. If not, I guess I will try
it on my own when I pick up some more zip ties. I need to also figure
out how to get the sensor pointed optimally from the rear stay. I also
recall someone posting a mod that essentially carried the signal
through a wire functioning as an antannae. One last thing is that I
can't figure out how to get the case off of the later sensors. I have
one that needs a new battery and Polar helpdesk won't tell me except to
send it to them.

TIA

Chris M wrote:
I have at least one each of the speed sensors from pre "S-series" and
first and second generation S-series. I started to use the latest
version of the speed sensor sold as the "S-series Speed Sensor 2"
mounted on the right fork blade. When I used a 710 (about 2001 model)
with a first generation S-series speed sensor (the first one molded
that mounts flush against the fork blade) I would get spikes in the
reported speed that would be corrected with the PPP error correction
tool. I would normally see an average of 2 to 3 spikes per hour of
road time. With the 720 and a Speed Sensor 2 I get almost no spikes.
I also noticed that I can wear the watch on my wrist and still get
both the speed and cadence to function.

It got me wondering if anyone has tried this latest sensor on the rear
wheel? I know that the signal is very directional and I recall that at
least one version had a 3 position DIP switch to control the signal
strength. Any feedback would be appreciated. If not, I guess I will
try it on my own when I pick up some more zip ties. I need to also
figure out how to get the sensor pointed optimally from the rear
stay. I also recall someone posting a mod that essentially carried
the signal through a wire functioning as an antannae. One last thing
is that I can't figure out how to get the case off of the later
sensors. I have one that needs a new battery and Polar helpdesk won't
tell me except to send it to them.

TIA

My speed sensor worked on the back wheel of one bike, but not on the back
wheel of another bike. Don't ask me why. Signal strength was high. S720i
year 2003.
I remember that antennae mod to. I'm sure it'll work. I never pursued this
any further since I bought the Power option and speedsensor on the back
wheel is default.
How to open? You need a *very* small Philips ( star ) screwdriver. When you
unclip the zipties you will see two small holes protruding inwards, towards
the fork when mounted. Fins a screwdriver that fits nicely in the hole. feel
very carefully that you have a good grip on the screw and untighten
carefully. Be careful with the seal when you take the two pieces apart, it
is reusable. You have to slide the circuit board out to get at the battery.
Not very difficult if you just have a light touch to the fingers ,)
You will also find the settings for signal strength on the edge of the
circuit board. It's not a DIP switch. I forgot what it's called in English.
It's this little doohickey piece that you move between some pins to make
contact between the right pair of pins. Move it to the outermost pair on the
circuit board to get maximum signal.


--
Perre
I gave up on SPAM and redirected it to hotmail instead.

Per Elmsäter wrote:


My speed sensor worked on the back wheel of one bike, but not on the back
wheel of another bike. Don't ask me why. Signal strength was high. S720i
year 2003.
I remember that antennae mod to. I'm sure it'll work. I never pursued this
any further since I bought the Power option and speedsensor on the back
wheel is default.
How to open? You need a *very* small Philips ( star ) screwdriver. When you
unclip the zipties you will see two small holes protruding inwards, towards
the fork when mounted. Fins a screwdriver that fits nicely in the hole. feel
very carefully that you have a good grip on the screw and untighten
carefully. Be careful with the seal when you take the two pieces apart, it
is reusable. You have to slide the circuit board out to get at the battery.
Not very difficult if you just have a light touch to the fingers ,)
You will also find the settings for signal strength on the edge of the
circuit board. It's not a DIP switch. I forgot what it's called in English.
It's this little doohickey piece that you move between some pins to make
contact between the right pair of pins. Move it to the outermost pair on the
circuit board to get maximum signal.

The "little doohickey piece that you move between some pins" is called a
jumper, :-). There are instructions on how to boost your speed and cadence
sensors' signal strength at
http://www.pursuit-performance.com.a...d_cadence.html

Warning, this will probably void your warranty.






J. Spaceman


--
My email address ) is fake. Email sent to it
will only get caught in my spam tarpit.

There are also instructions at
http://www.roadcyclinguk.com/news/ar...98264342380256
with nice big, clear, step-by-step pictures that you can click on.




J. Spaceman


--
My email address ) is fake. Email sent to it
will only get caught in my spam tarpit.

If it works fine on the front wheel, why would you want it on the back?
I can't see the advantage.

How can you tell the difference between the two sensors? I tried
hooking up a sensor on one bike with a 5" travel fork, and couldn't get
a decent signal. Same sensor works fine on a XC fork, and on a roadie
bike. A better sensor might fix that.

wrote:
If it works fine on the front wheel, why would you want it on the
back? I can't see the advantage.


Did you ever use a Trainer?

--
Perre
I gave up on SPAM and redirected it to hotmail instead.