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is the front brake switch. They work normally for maybe 6 months, then they start to act up (I can hear arcing interfering with the radio - normally, but not always, when they are supposed to be on). Then with switch cleaner or WD40 etc. they will work for a few months more. Then they stop altogether. I have opened a few up over the years and the contacts are always black. My bike leads a hard life, used in all weathers and parked outside, but the switch arrangement is pretty well protected so I don't see that water could be the problem. I don't get much better performance from rear brake switches, but that's understandable given the crud that gets into them. Surely I can't be the only one?

Inever have had one fail.........and got my first BMW in 77.....

I reckon that the most unreliable component is the guy who works on the bikes, and that's me. otherwise it it is the electrical connection at the starter relay, I reckon that 75% of all BMW electrical problems originate there.

I figured this was going to be about the rider.

WD40 is NOT what I would spray on any electronics, over time it leaves a gummy residue.

Tim Shepherd wrote:WD40 is NOT what I would spray on any electronics, over time it leaves a gummy residue.

Yes you are using a poor product for your problem. WD is a good cleaner but it won't prevent your problem. I like Fluid Film for those problems but it may not be available where you reside.

yes W-40 is quick cleaner BUT not to leave for the job, carb cleaner or contact cleaner after is the point for useing w-40

grease connections and proper clean is the way to go

Don't use WD40 for electrical use. That's not what it was designed for and it doesn't do a very good job often causing more problems than it solves. Get some electrical contact cleaner.

Rob

I have used proper switch cleaner on the last few switches, it doesn't make any difference to the life.
Anyway, that's not really the point - it's just a switch and I would expect many years trouble free operation with no attention (like every other japanese bike I've owned).

I note Chasbmw has never had one fail - if that's typical then I must have some underlying problem although I can't imagine what.

I haven't had one fail either, not even on the '71 R75/5.

Mine are at least 22 year old, or they may be original, 38 years old. Maybe you have a wiring issue.
The 47 year old rider is the least reliable part, not German, made in the USA, but British ancestry.