Speedo not working (not water related)

[Padowan]

Speedo has packed up on the wife's 03 non-ABS F650GS Dakar.

It uses the rear wheel (ABS if it was fitted) sensor.

I've read that they can be temperamental if wet, but that's not the case here, the bikes not been wet for months and is stored in the garage. I've had a meter on the sensor terminals and was looking for some AC volts when spinning the wheel, but nothing. The sensor gap is within spec at about 0.7mm.

A while back the rear wheel bearings collapsed and the slotted disc was merrily grating away at the face of the sensor, the sensor looks OK, with only minor "sanding" on the face - it's clean and I can't see anything exposed. I'm pretty sure that a new sensor will fix it, but I'd like to troubleshoot to be sure before shelling out $$$ for a new or used one.

Any ideas whet else to check?

Simon

 

[Padowan]

Bump. Any ideas of what else to check before I commit to buying a new sensor? Particularly, how can I test if any wear to the face has compromised the operation of the sensor?

 

[Timolgra]

A while back the rear wheel bearings collapsed and the slotted disc was merrily grating away at the face of the sensor, the sensor looks OK, with only minor "sanding" on the face - it's clean and I can't see anything exposed.

So has it worked since the bearing collapsed and damaged the sensor?!?

 

[Padowan]

It was working fine before, then intermittently at the time the bearing collapsed. Not the brgs have been replaced and it's all reassembled it's now not working at all.

I'm sure it's damaged, but I'd like to be able to test/validate that's the case before shelling out about £70 for a new one.

 

[Timolgra]

The pick up disc needs to be fairly true, check the gap at every slot/tooth, if it's the thin one you can bend them to get the gap if needed.

 

[Dansin]

It's probably goosed but also worth checking the wiring loom where it loops around the headstock. If the ties are tight the wires have a tendency to chafe or break.