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When you install the replacement, double check the connections to the GPS on the bike. That is a possible location for resistance problems and changing values are what changes the display. Just in case the new part doesn't fix it (I'm sure it will), you can check the ohms with a meter at the plug while changing gears by hand. If they jump around erratically while still in the same gear, or has different values each time you put it back into the same gear .... the switch could be worn/loose inside.