Another wobbly speedo

[Me-109]

And I'm not talking swimwear!

Been along the road to get my yearly certificate this afternoon and noticed my speedo giving a 10-15mph variation in speed without the back wheel similarly spinning up or the engine picking up revs. I've done the search which suggests a cable or connector under the seat/panel, rather than the sensor itself. Hopefully this is the case. It's not moved much over the past couple of months but has been on an Optimiser. I wonder if this is just a charge-type issue (no ABS lights coming on, but they are separate senders)?

If it's not too cold I may get myself into the garage later and investigate the wiring.

[timbox2]

Part of the service schedule is to take the sensor out of the diff carrier and give it a clean, Id probably do that first, actually I wouldnt as the bolt that holds the sensor in on my bike has sheared and its glued in with Araldite

[Me-109]

Yep, done that as part of the servicing and elsewhere when I've changed the rear wheel bearing, the output shaft seal and the rear box oil.

Anyway I did it again last night, then traced the wiring up behind the panel to the connector. I barely touched the connector and the brown wire on the harness side snapped. Extracting the terminal to make some repairs snapped the yellow wire .

The ends were a little stiff but otherwise clean. Stripping the wiring back a little and baring some fresh copper I resoldered the terminals and rebuilt the connector. I could only test it by spinning the rear wheel by hand and I can see the speedo moving, so at least a signal is getting through. Until I get it back on the road I can't be sure it's properly fixed, but the ease with which the wire snapped in the first place suggests that was the fault.

Oh .... and then I was able to fit my nice new (used) tankbag.

[winny2]

Mine did the same a few months ago. The speedo got more and more erratic until it stopped working completly. I traced the fault to the same brown wire which had snapped.

However, I now do have a spare sender unit and wire, should you need one.

John

[timbox2]

see, I shouldnt have spoke so soon, started the bike up just now, as Im warming the engine up I notice that the speedo is behaving like the Tacho, now I know the s looks fast standing still, but I got it up to 80 without moving.

Ran the bike round the block and its Ok now???????????????
Maybe I need to look at this wire?