cycle computer problem

my cycle computer goes nuts every time i start my engine. has anyone else had the same problem? i would really like to get it working so i can use the odometer function to see how far i go each day.

this is my computer Bike Bicycle LCD Cycle Computer Odometer Speedometer - eBay Cycle Computers, Universal Parts, Accessories, Cycling, Sport. (end time 07-Jul-08 21:00:11 AEST)

Coil the wire as you run it up the forks/bars. You can also use a sheilded plug cap and/or a resistor plug.

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If it ain't broke, and you mess with it long enough, it will be.

If you can also keep your computer wire as far away from the plug,plug wire CDI and wires it will help out alot also.

Mule: If you have the type that snaps in and out of bracket on the handlebars you may want to check to see if the vibration isn't messing with the contact points.I have a Cateye and that was causing all kinds of crazy readings

I took a tip from the very cars I work on. CAN bus wires are twisted together to shield them. So, I twisted mine together keeping the twists about a CM apart. Now my tripmeter no longer malfunctions.

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48cc Giant. 50T, 26" wheels, catalytic converter-Built for Younger brother.

66cc Trek 800. 44T, 26" wheels, cut baffle. Top speed 35.0mph.

it is the magneto .. i experimented a bit and found if i sheild the wire with an earthed sheet of foil it works fine. im looking for a neater fix, the "aliens cant read my thoughts" look isnt for me. any one tried a ferite ring from an old playstation controller?