Turn FR into bike meter

[Anthony Clearn]

Risto H. Kurppa wrote:
> 
> 
> 1) I'm missing the cadence display...
> ...-> any ideas how to build this
> planning to do a 170-200km bike trip in a day :)
> 

Here are some ideas:

as an extension of the above post:

Place a Neodymium Magnet 1mm on the crank and as has been said a hall sensor
fixed perhaps behind the bottom bracket cup with the wire routed along the
inside of the frame, out via seatpost or headset cap or breathing hole,
mount point, etc. Epoxy resin / cyanoacrylate might hold the magnet in place
to avoid drilling, as it may not be a good idea to cause a weak spot in your
cranks!

You might want to check out how ABS works also, afaik basically a toothed
wheel and hall sensor - which might mean the crank arm would cause a pulse.
I'm not sure about this

On a different tack, how about an optical sensor from a mouse / printer?
This could be a good use of an otherwise redundant piece of computer waste.
:) Though dirt may be a problem here. Also I can't see how to mount it
easily.
 
While your at how about some strain gauges and some  glue
http://en.wikipedia.org/wiki/Cycling_power_meter

Best of luck on your cycle, are you using opencyclemap? Where are you
cycling?



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