Be careful with the wireless bike computers. I am currently looking to install a bike speedo and thought the wireless models would be perfect, but I think you need a clear line-of-sight between the magnet sensor and the display unit. Also, the range of the unit I looked at was 70cm, far too short to go from wheel to dash. Even if you didn't need a clear line-of-sight, when you throw all the interruptions from the electrics/ignition system into the equation, I think this will corrupt the signal too much for an accurate reading? Please correct me if I am talking crap!
I have been looking into the possibility of using a Palm Pilot as a speedo, as there is a company that makes software and sensors/magnets to turn your PDA into a digital speedo/odometer/navigator. Don't know if anyone has tried this with a car, but it looks like a pretty cool toy and I guess you could program it to do nerdy things like 0-60 timings. I have no reason to replace the VDO analogue speedo, as it seems to be working well, I am just a sad geek who has a bit too much time on his hands at the moment!
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