Brake light is stuck ON.

[DeeG]

I have noticed over the past two years that the brake light sometimes doesn't release (go back to taillight only) after I let go the handle. So, as I was waiting for the oil to drain yesterday, I started investigating.  

I have found that there is a switch/plug of some sorts just behind the fork assembly.  I has two wires coming off it, both of which eventually end up at the brake light.  I unplugged one of the wires and voila! the brake light went off, and the taillight was on.  I pushed down on the foot pedal, brake light comes on, and when released, brake light goes off.  Of course, when you use the brake handle, no light.  If I plug the wire back in, the brake light goes on.  

So.

Is this switch/plug defective?  How do I fix this?   The switch/plug is in some sort of rounded metal casting, it reminds me of a three way valve for your garden hose.   Maybe take apart the brake lever and bits on the handle bar and clean it up?  

Can't find the camera, maybe there is an exploded view somewhere on the web that I can find......

Thanks

Dee

[Bob_Roller]

You most likely have a bad brake light switch at the handlebar lever .

You can remove the round switch, first remove the rubber boot covering the wires, remove the wires, use a piece of cloth or other material, and a pair of pliers, it just threads out .

You can try cleaning the switch up by placing it in some alcohol, and activate it by pushing the pin in and out .

It may unstick it, but more likely you're going to need to replace it .

[Justin B.]

You did not give the year of bike - very important as the switch changed in 1981.  The 1979 - 1980 switches screw into a splitter and are actuated by hydraulic pressure.  If this is your type then you will likely need a new switch...

[Bob_Roller]

I'm going to have to say it's the R45 she's talking about, and from the signature line, it's a '78, so it is the brake pressure switch, not a mechanical switch on the handlebar .

Not much to do there but replace it .

You'll need to bleed the brake system after replacing the switch .

[Lucky_Lou]

Buy a new switch they are not expensive the circuit is independant to the front and rear you will need to bleed the front brake after fitting it
http://www.motorworks.co.uk/bmw/products/product.php?f=i&code=BA_15_20_IA_50&shnew=New&model=R45%2F50%2F60%2F65%2F75%2F80%2F90%2F100+%282+valve%29&shnewcode=15&part=Electrics&sub_part=Brake+light+switches&modelcode=20&partcode=IA&source_code=BA_15_20_IA_50&header_text=&header_text_image=0
scroll down the page you will see the the part no.ELA44334
Lou

[MrRiden]

Guessing here but for a 79 R45 it is. Part #10 in diagram. It is
BMW part 61311244334. You will also need Gasket ring not shown. Part#07119963073 On REAL OEM http://tinyurl.com/mol82d

[Justin B.]

Rich, that's the one.  This was constantly "on" on our '80 when we bought it...

[DeeG]

Yup, that's the part.  

Got the part on order, and I also ordered up a pair of Speedbleeder valves so I don't have to have another warm body help with the brake bleeding.  

THANKS GUYS!!!!    

[drgnfli]

I changed my brake light switch with a part from NAPA.
It's a direct replacement and fit.  Part # SL143 and cost
about $15.00.  Beats the original BMW part which cost
about $36.00.   Been using it for 4 monts now and no
problem.  You can search NAPAonline (type ECH SL143 on
part search ) and you can see it is almost identical
to the original part.  Hope this helps....

[Justin B.]

Did NAPA tell you what it's application was?  Just curious...

[drgnfli]

Brake light switch for mid 60's VW Beetle....

[Justin B.]

Interesting, I had no idea they used a switch like this.

[drgnfli]

Did a search and the following vehicle use this part also:

1966 -  VW Karmann Ghia
1970 - VW Beetle
1972 - 1976 Porsche 911
1982 - VW Rabbit
1983 - VW Vanagon, Jetta, Rabbit
1984 - VW Scirocco
1989 - Porsche 911