Polar wireless sensor - is my new one dodgy?

kenbaxter
kenbaxter Posts: 1,251
edited January 2008 in Workshop
Set up Polar CS200 Cad thanks to some help from folks here - many thanks. All appears to work fine BUT, speed sensor works cuts out below about 12-14kph. Works fine at speed but when start climbing it zeros. Not usually a problem but on a 2 hour ride in the Cotswolds I lost about 20 minutes of recorded riding. If I put the bike in a stand and spin the wheel it records down to about 4 kph only if the computer is a couple of inches from the sensor, but up on the bars it cuts out much earlier, in fact it only records low speeds a couple of inches away, anything in between this and the bars and it loses them. Am guessing that the range doesn't work for these low speeds but given that it can't be mounted 2 inches away, is this a symptom of a dodgy speed sensor/low battery or does anyone else have this problem? If its common its not exactly a great design feature and given that most of my riding is in the hills, not exactly useful.

Thanks (as usual!)

Comments

  • Garybee
    Garybee Posts: 815
    It could be worth trying a new battery in the sensor. Often you get really naff batteries in new bike computers, I imagine it's down to manufacturers saving money.

    Hypocrisy is only a bad thing in other people.
  • kenbaxter
    kenbaxter Posts: 1,251
    Trouble is sensor is sealed so flat battery = new sensor! Wondered if this is normal behaviour before I go knocking on Polars door in Warwick (again - although they were good last time!).
  • Garybee
    Garybee Posts: 815
    kenbaxter wrote:
    Trouble is sensor is sealed so flat battery = new sensor! Wondered if this is normal behaviour before I go knocking on Polars door in Warwick (again - although they were good last time!).

    Ah, see what you mean, that's a bit different then. There's no way that that could be normal behaviour though, it should be perfectly capable of transmitting down to very low speeds. How close is the sensor to the wheel magnet as it passes?

    Hypocrisy is only a bad thing in other people.
  • kenbaxter
    kenbaxter Posts: 1,251
    As close as it will go without touching it. Signal at speed is fine, and up close all works OK. Just drops lower speeds when on the bars which doesn;t seem right - and is somewhat annoying! Cadence sensor (which was replaced last week as the one in the box was dead) will now happily pick up down to very low cadence and is further away so me thinks the speed sensor is dodgy as well.
  • Garybee
    Garybee Posts: 815
    It does sound as it you've been given a duff one. Just a thought though, have you mounted it on the front or rear wheel? Some wireless sensors are ok for rear mounting :lol: but most aren't.

    I'm surprised that the batteries aren't replaceable as wireless sensors use a relatively large amount of power. I wouldn't expect them to have a good lifespan really.

    Hypocrisy is only a bad thing in other people.
  • It sounds like a dodgy speed sensor if the cadence sensor was faulty, I take it you have the speed sensor as near to the bars as you can get it?