1. The most important thing about buying a new bike is to make sure it fits. The only way you'll know if the bike is right for you is to size up the bike and make sure that the bike's geometry matches your body's geometry. Ask questions and do some research.
mtn. biking 101
2. If possible, try to find a shop that will let you demo the bike on real dirt. Five minutes in a parking lot won't cut it. You wouldn't buy a car without a real world test drive, and a bike should be no different.
3. Don't belive the hype. Just because your favorite rider or best friend rides a certain bike, that doesn't mean that's the best one for you. Have an open mind and be realistic about your needs and ability.
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  1. #1
    Clyde and then some
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    Installing Computer - Best Sensor Position

    So I picked up a Cateye Strada Wireless as a present for the wife (ok, I'll admit it, I'm also using her as a guinea pig to see if I like the model) and was getting ready to install when I thought of a question.

    Is there an advantage to mounting the sensor higher or lower on the wheel? I was originally leaning towards the top of the fork near the rim, but then it occured to me that technically, the sensor would be moving slower, and in theory more accurate if I put it nearer to the bottom of the fork and closer to the center of the wheel. She's on a 17.5 with 26", so the distance is within the 70 cm range. Is there much benefit to installing closer to center, or are these things good enough to pick it up at the edge?
    Remember, no matter where you go.... you're not where you were anymore.

  2. #2
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    Technically? Actually if you place the sensor near the rim, it will rotate faster, but for a larger distance. Whereas the location closer to the hub will move slower. Either way, it's a point on the wheel, and all those points make a single rotation in the same amount of time.

    Just pick a spot and line up the sensor with the magnet. Whatever works best for your fork/brake/wheel setup. The magnet must pass the sensor, and your computer must be calibrated for the size wheel you're running. Cat Eye's come with pretty detailed instructions for measuring the circumference of your wheel.

  3. #3
    Clyde and then some
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    Quote Originally Posted by MrMook
    Technically? Actually if you place the sensor near the rim, it will rotate faster, but for a larger distance. Whereas the location closer to the hub will move slower. Either way, it's a point on the wheel, and all those points make a single rotation in the same amount of time.
    Which was kind of my question. I was wondering if the fact that in an outer position, the sensor moving faster would create a higher chance for missed reads. I went ahead and mounted near the center as it looked cleaner anyway.
    Remember, no matter where you go.... you're not where you were anymore.

  4. #4
    What could go wrong ...
    Reputation: Zoke2's Avatar
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    the higher up the fork leg you mount the sensor the farther away the magnet will be from the sensor --- as you move up, the spokes angle away from the edge of the hub to the center of the rim. I mount them low so i can get the magnet as close as possible to the sensor
    I used to ride to Win ... Now I ride to Grin

    While my guitar gently weeps, my bike sits there mocking me

  5. #5
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    The unit I just got from performance only goes up to 28" wheel with tire mounted, I assume this is correct for my 29er?

  6. #6
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    Reputation: nomit's Avatar
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    Quote Originally Posted by Zoke2
    the higher up the fork leg you mount the sensor the farther away the magnet will be from the sensor --- as you move up, the spokes angle away from the edge of the hub to the center of the rim. I mount them low so i can get the magnet as close as possible to the sensor
    the strada wireless has a pretty big sensor box that you can rotate around the fork until it's within the desired distance to the magnet (a hairs width, 1mm, 5mm...etc)

    Which was kind of my question. I was wondering if the fact that in an outer position, the sensor moving faster would create a higher chance for missed reads. I went ahead and mounted near the center as it looked cleaner anyway.
    then you could ask the question...
    is having the wireless sensor mounted at the far end of the 70mm more likely to give you 'missed reads' because you're pushing the limits on its coverage area?

    i don't think either matters that much...and are you really worried if it misses one rotation out of every 5,000?

  7. #7
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    Speaking from a more roadie viewpoint: you'll want that magnet as close to the center of the wheel as you can get it, o.w. it will introduce a noticeable wobble as the wheel spins. On true mtn. biking trails, you probably wouldn't notice it. But, commuting, I found it to be rather irritating.

    And, as previously mentioned, when nearer the hub, the magnet and sensor will be in closer relation to one another, and the velocity of the magnet will be slower.
    - Eric

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