Speedo not working.

just wonderin if anyone can help? my speedo has stopped workin and it has also stopped clocking up the mileage. i still have the time clock and temp readout so its obviously a speedo problem. Is this a common fault and fixable or am i looking at having the whole thing replaced?

[dirtydog]

It's more than likely it'll be the speedo drive down at the front wheel. It's got a plastic rotor in it and they're well known to break

Thanks to dirtydog for answering my initial post but unfortunately ive changed the drive rotor (the old one looked fine but seeing as though id already bought the new one i changed it anyway) and no joy. Sometimes the speedo starts fluctuating ranging from 1 to 186mph even though im not moving and the mileage also moves up. could it be the cable? does the cable go into the brain and then back to the dash or does it go stright into the dash? (weve tried following the cable but cant work out where it goes without taking it all apart). would really appreciate if anybody has any ideas as dont fancy paying for a full diagnostic if its something silly.

If you have a search you'll find my thread when I had a similar problem. My rotor was mangled, but putting in a new one didn't make any difference. It turned out I had to replace the whole sensor unit down by the axle, including the wire that runs into the headlight (on a naked K3 in this case). Somewhere along the cable and the sensor mechanism it was broken. Fixed it with a curvey spare one, although the fit isn't perfect and needs a bit of carving.

Here you go

thanks for the heads up mate. guessing that the cable doesnt go into the brain first then (even though it seems to disappear just above the engine) must double back under the tank and into the dash. will get a new cable and sensor and try swappin over.

I have this as well , on the right hand side of the airbox is a Sensor or something , it is a Green coloured plug near the box , one of these cables may be duff , I give mine a jiggle and it cures it til I can get in there and have a good gurn at it .