www.boxertrix.com

Any thoughts anyone? Two days ago myspeedo stopped working properly. Occasionally it reads OK, but if you wind on a bit it goes all over the place and drops back to zero. Most of the time the needle just sits at zero and I don't like having to estimate my speed! My first thought is that the sender is on its way out, as it looks like it's picking up readings intermittently.

I see Motorworks list a preowned sender for 12 notes.

I had a very similar problem on mine.
Sawbridgeworth BMW replaced the sender to no effect and it turned out to be a wiring problem possibly initially caused when I crashed a few months previously.
For £12, it might be worth trying the sender first though.

Thanks Vincent

My local dealer has run a diagnostic (!) and is convinced the sender is dud. Motorworks don't actually have a used one in stock so that'll be £41 from BMW, then, plus fitting.

Hi check the wiring which goes to the sender.Especially where it is tie wrapped to the frame.The ties can be too tight causing chaffing(i love that word).Also if it is the sender unit,fit it yourself.It is one bolt and a few tie wraps.Also try wd40 on all the connector blocks,could be corrosion.
gus

Thanks Gus. I did a bit of a check on the wiring myself and cleaned the connectors I could get at without removing bodywork but it made no difference. I'll try again later and see what happens.

Follow the wire up from the sender under the seat to the connector block. Pound to a penny that the yellow (I think) wire is chaffed on the other side of the connector - mine did the 'mental' thing for a while - the wire is now 'hard wired' (ie cut and taped together ) avoiding the connector block.

I discovered that if I packed too much under the seat it would interfere with the sender cable (this is on a Rockster) - make sure there's nothing interefering with the cable run.

Dear all

I got it fixed - it was the sender. Diagnosed, supplied and fitted for £50.00, which isn't exactly cheap I know, but I couldn't find a used one. They charged me a tenner to fit it, which is 10 minutes at BMW rates Thanks for the help and advice.