Bicycle computer/speedo problems......

Discussion in 'General Bike Discussion' started by greenhorn, Mar 17, 2010.

  1. greenhorn

    greenhorn greenhorn

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    Sure I hope I don't sound like an idiot here but I ran into something this week that has me scratching my head. Been riding for a few years, mountain bike, then a hybrid and just bought my first road bike. I have always installed a cheapy computer or speedometer on these bikes, usually the wireless variety and have never had any trouble. I recently bought 2 from different sources and can get neither one to work on the new bike. The one computer registered 675 miles over night last night....sitting on my TV. No sleep mode, very strange behavior. I tried different new batteries, both operate very strange. Is it possible I just got 2 bad computers or am I missing something? Any suggestions? The only variable I can think of is this bike has a carbon fork but I can't imagine that's an issue.
     
  2. Industry_Hack

    Industry_Hack Total noob (& forum admin) Admin Staff Tavern Member

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    Wireless computers are subject to radio interference. It probably says something about Class B, and having to accept interference, but cannot cause interference.
     

  3. dcswan

    dcswan New Member

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    I had got a fairly cheapo wireless one awhile back and didn't have any trouble with it jsut sitting there like you explained. I had trouble with it on the bike though, it wouldn't register the miles then all of a sudden jump to some random number. Did the same thing, tried different batteries at first, then just had to accept it was a dudd but couldn't exchange it since I had already got rid of the pakage for one. Plus this while I was stationed in Korea and had to get it from the Base Exchange at the base 3 hours north of me, so had to get an even cheaper one that is still working, for the most part! LOL Never had anything carbon so can't speak on that part of it. Maybe try reseting it and keep it off the TV, electronics are wird and do things someting one wouldn't think of happening, that's my only thought besides returning those (if you can) and spend the few extra bucks for a better brand name with a better track record.
     
  4. greenhorn

    greenhorn greenhorn

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    Hack, I never installed one of these in my study before, always down in the garage. Do you think the TV and wireless cable box might have been the issue last night? Lots of signals in the airways in that room. Might have to try it again downstairs and away from all the "stuff" in that room.
     
  5. Industry_Hack

    Industry_Hack Total noob (& forum admin) Admin Staff Tavern Member

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    Try that, I'm sure it's your wireless gear interfering.
     
  6. jagonz456

    jagonz456 New Member

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    reset wheel size

    you need to reset the computer and change the wheel size if the wheel size is off your calculations will be off as well. mount the receiver on the left hand of the fork some bike computers need to be mounted on the left hand side. You got a nice bike treat yourself to nice computer you can't go wrong with cat eye. If you get a digital computer you don't have to worry about any interference.
     
    Last edited: Mar 17, 2010
  7. kjargo

    kjargo New Member

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    Other Options

    Everyone's suggestions seem to be spot on. Unfortunately, despite most manufacturer claims, many wireless computers are susceptible to to interference. The only other issue I can imagine would be if excess sweat and moisture is getting onto the computer/mount. Some computers have the wireless receiver as part of the mount rather than in the computer. The sweat could short the signal, but you would likely see other issues beyond just skewed distance.

    If the issue persists, try a computer with a coded signal or 2.4 GHtz ANT+ wireless signal. Otherwise, you can't really go wrong with a solid wired computer. They work great, but do look a littler less Pro.

    Kevin Jargo
    Product Manager
    Vetta/Acumen Inc.
    Welcome to Vetta
     
  8. Industry_Hack

    Industry_Hack Total noob (& forum admin) Admin Staff Tavern Member

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    I suppose Kevin would know... ;)
     
  9. wild

    wild Yesterday tired old man, Today retired old man

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    I would say it is from the TV putting out magnetic radiation EMF. I know if I walk real close to my TV the hair on my arm will stand up:D
     
  10. BlazingPedals

    BlazingPedals Member

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    I once parked my bike near an electric fence at a supported ride. While I ate a few cookies and had a cup of lemonade, my wired computer registered ten minutes' riding at some ridiculous low speed. That really screwed up my computed average speed for the ride! I later figured the EMF field from the hot wire was closing the reed switch on the sensor. Electric fences are pulsed at roughly once per second, which meant it was registering one wheel revolution per second, or about 3-4 mph. So the moral is, even wired ones can be affected (although wireless is more susceptible.) A television has some very high voltages running around in it. It'd be best to keep any computer well away!
     
  11. greenhorn

    greenhorn greenhorn

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    Well I don't want to keep anyone in suspense....Industry Hack was exactly right with the TV and wireless cable box. I took everything down to the garage and the installation went great. No wacky behavior and calibrated nicely. Took it for a spin around the block and had absolutely no trouble.
    Thanks Hack, and everyone else for bailing me out with this one.
     
  12. Industry_Hack

    Industry_Hack Total noob (& forum admin) Admin Staff Tavern Member

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    Please, send a link of this to my ex-wife. :p


    Seriously though, glad you got it sorted.