Wizard,
This might be "but-ugly" to some but what do you think of this:
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This is dead on accurate for giving your speed plus an additional odometer and all kinds of other functions like riding time, accumulated riding time, time of day, average speed, max speed and so on. At the push of a button you get a whole "nuther" duplicate set of readings for another bike or you can use the "bike#2" feature if you want to measure a "sub-trip" while on a long ride. I've never done this but I'm just pointing out all of the "shi." you get for so little money. If this was made for a motorcyle you'd pay at least (hell, I don't know exactly) but probably $200.00 or so. The picture shows mine installed on the handlebars between the risers.
Here's a pic of the sensor attached to the fork (I am planning to do a better job on this (manana), but this is how it is now). You can also view the magnet on the hub. Just a dot of epoxy holds it on.
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You get all this for $39.00. You can also get these computers for as little as $12.00.
-Don
