Rev and speedo needles going up and down

[oldmotherfoccer]

OK Deefer666 says that depending on where the needles point it is one of 3 things

1) TPS Faulty and the rev counter needle will give the fault code
2) The magnetic tips breaking up from the ceramic drive dog (very common if the front wheel has been removed by an unexperienced mechanic)
3) The speedo sensor wire wearing through on the brake discs due to being incorrectly routed