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Defender of Freedom...
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Discussion Starter #1
Just curious, I have several bikes with the exact the same wireless computer and varying distances from sensor to the handlebar, all of which are probably within an inch or so of each other. Here's the question, does anyone have what they consider the perfect distance front the front hub for the sensor/magnet placement? Inquiring minds want to know...
 

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It just counts revolutions and calculates using the stored wheelsize, so position has no effect on accuracy, so long as the magnet passes the sensor close enough to register. With any wireless transmission, the closer the better.
On my wired computers I always try to get the magnet as close to the hub as possible, with some irrational justification about rotational mass, though I know the .5 gram isn't going to make a lick of difference.
I've never had luck with wireless, but you raise an interesting question. Maybe I should try one with the magnet mounted near the rim to get the sensor closer to the computer.
 

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Not much difference

If the magnet is closer to the hub, then it will be moving more slowly when it passes the sensor and therefore give the sensor longer to register the "click" of a wheel revolution. That used to be an issue with bike computers, but things have improved to the point where it really doesn't make a difference.
 

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Defender of Freedom...
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Discussion Starter #4
With a smaller magnet...

Kerry Irons said:
If the magnet is closer to the hub, then it will be moving more slowly when it passes the sensor and therefore give the sensor longer to register the "click" of a wheel revolution. That used to be an issue with bike computers, but things have improved to the point where it really doesn't make a difference.
that might actually be a good thing. The one negative I have experinced with the micro magnets is having to tweak the sensor in a bit to get it to pick up. The downside is I can usually ping the magnet when the wheel flexes on out of the saddle efforts. Do you think moving the magnet sensor down the fork closer to the hub might help with better pick up and decreased contact with the magnet?
 

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What do you think?

Ramjm_2000 said:
Do you think moving the magnet sensor down the fork closer to the hub might help with better pick up and decreased contact with the magnet?
Do you think that it is possible to have much wheel flex close to the hub? To me, it seems unlikely. Closer to the hub would obviously solve this problem.
 

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Defender of Freedom...
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Discussion Starter #6
That's what I'm leaning towards...

moving the sensor down will probably improve the "pinging" and by default move the magnet closer to the sensor. How far from the hub are you running yours?
 

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Ramjm_2000 said:
moving the sensor down will probably improve the "pinging" and by default move the magnet closer to the sensor. How far from the hub are you running yours?
I have regular 3x laced wheels. I put the magnet in the crotch of the second crossing out from the hub. The "V" nicely cradles the magnet, keeping it from twisting on the spoke.
 
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