• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

Brake light switch

dennypink

DennyPink
After 21 years the rear brake light switch on my 1992 RT has gone ka-put. I can't figure out how the switch is attached to the bike. Looks like I need to remove the battery to access the switch and the gas tank for the top plug in portion. Can anyone shed some light? Thank you!
Denny Pink
32,167
 
Last edited:
The rear switch on my 85 R80RT gave up a few years back. I can't recall if the lead from the switch was long enough to end under the tank or behind the side cover. Near as I can tell, our bikes are the same as far as the rear brakes go.

The attachment of the switch is pretty simple, but it is difficult to get at. It might help to have a lift table so you can come at it from below. Removing the rear wheel and swingarm would probably give better access, but that's an awful lot of work just to be able to get at that switch. The nose of the switch (with the plunger) is threaded and the threaded nose goes through a hole in a mounting plate and then a nut goes onto the threads from the plunger end to lock the switch in place.

Since the whole works is behind the frame plate that holds the rear brake lever pivot plus the passenger foot rest and right up against the swingarm, it's just hard to see what you're doing. Pulling the brake foot lever off and cleaning everything up will help. With the brake lever out of the way you can see/feel the switch. I found it difficult to swing a wrench in there between the frame plate and swingarm to remove and replace the nut that keeps the switch locked into it's mounting hole - but, I did it.

Perhaps someone else has a slick way to get at this switch?
 
Last edited:
Thank you Mono RT for your great instructions! I ended up removing both mufflers, rear wheel, right side cover, shock, and rear brake pedal. Removing the shock allowed me to lower the rear drive a little, resting it on some boards, and giving me more room to work. You were correct, it is a tight space in there. Removing the old switch and installing the new one (part # 61-31-1-459-569) took about 15 minutes. The remaining 3 hours was disassembly-cleaning-reassembly. Now I have a good switch for another 21 years, and my brake pedal pivot is clean and greased. I also pulled the rear brake cam shaft and cleaned/greased that as well. The best thing was, no left over parts when I got it all back together. One more thing, according to BMW shop rates, this is a 66 minute job.

Denny Pink
 
I just discovered that my rear brake light is staying on all the time. The switch itself seem to be good, the problem appears to be that the finger on the brake pedal that presses on the switch plunger is out of alignment and not pressing. It seems to be off to one side. Not sure how/why that would happen but I'm going to be removing the rear wheel to replace the rear brake rotor next week so that might be a good time to attack this problem. Should be fun...
 
front and rear brake light switches

I just discovered that my rear brake light is staying on all the time. The switch itself seem to be good, the problem appears to be that the finger on the brake pedal that presses on the switch plunger is out of alignment and not pressing. It seems to be off to one side. Not sure how/why that would happen but I'm going to be removing the rear wheel to replace the rear brake rotor next week so that might be a good time to attack this problem. Should be fun...
******************************************************************************************

For those that do not know, BMW had a recall campaign on the switches. It affects Airheads and K bikes, although a bit differently.
Here is my article on it. Read the ENTIRE article.
snowbum

http://bmwmotorcycletech.info/brakeswitches.htm
 
Back
Top