Front Brake Light Switch

[Jim Malm]

During a ride yesterday, my riding buddy told me my front brake light was not working. I confirmed that he was correct, but determined my rear brake light is still working. I don't have a good parts or service manual for the bike and currently am at a loss on where to start trouble-shooting this problem. It appears that there is a switch right at the the lever, but it is so small and simple looking that I'm wondering if this is really the case. There are two wires that seem to enter a small plastic enclosure under the fulcrum end of the lever.

 

I installed Convertibars on the bike and am wondering if prehaps I didn't pull a wire out of it's proper location when I did that.

 

Any suggestions on where to start and how to proceed in tracking the problem down will very much be appeciated.

 

Thanks!

 

Jim Malm

[Guest ratchethack]

Jim, one of the easiest checks, if you've got the bike in a quiet, enclosed area, is to put y'er ear up to the switch and slowly squeeze the brake lever. You should be able to hear the make/brake rocker in the microswitch closing and opening the contacts. This'll at least tell you if the switch is operating. Often times crud gets jammed in the windward side of the actuator, disabling the switch. There's either a tiny ball-bearing, or a tiny puck-shaped gizmo that resides in a hole in the brake casting that actuates the microswitch. If you take the lever apart for inspection and/or cleaning and/or lubing, be VERY careful. These tiny things have an uncanny ability to drop out onto that perfect spot on y'er instep, where it will take a lightning-fast dive toward the exact point, within about 300 degrees of the compass, where it's the deepest, and darkest possible part o' y'er environment -- o' course, never to be seen again.

 

If it's not the switch, it's more'n likely one of the bullet connectors in the wires leading to it that needs cycling, a bit o' dielectric grease, and a gentle re-crimp.

 

Good luck.

[Jim Malm]

Thanks for the quick reply. It sounds like you may have experience with this problem. I hope that the solution is as straight forward as it appears. I'll give your suggestions a go tomorrow and hopefully not lose too many micro parts in the process. Thanks again for the help!

 

Jim

[Greg Field]

Jim:

 

There's also adjustability built into the switch, via the screws that fasten it. Play with that a bit in listening for the snick of the switch, as Ratchet has told you.

[Jim Malm]

Greg-

 

Thanks to you too for that tip. I'll post my success or lack thereof to the forum.

 

Jim

[RonV11]

This has happened to me... Turned out to be the connectors to the micro switch. They looked like they were connected, however, they were not. Pushing them back on fixed the problem.

[Jim Malm]

Ron-

 

It sounds like the problem may not be as daunting to solve as I thought it might be. As I mentioned in my original post, there's probably a good chance I pulled the wires lose when I installed the Convertibars. Thanks for your reply.

 

Jim

[dlaing]

just a warning...if you take the switch off, the ball bearing will seek out the only hole in your floor where it cannot be retrieved :!:

FWIW some posts of replacement switches.

[mdude]

when grime gets into the microswitch, the ball gets stuck. a healthy dose of WD40 from time to time will prevent it.

[Guest Nogbad]

If you look at my post in the thread link Dave posted above, you will see that a version of the switch with "potted" leads is available. This eliminates trouble with the exposed micro-spade connectors on the standard switch. I have one of these potted lead switches on my clutch lever and it hasn't given any trouble at all.

[dlaing]

If you look at my post in the thread link Dave posted above, you will see that a version of the switch with "potted" leads is available. This eliminates trouble with the exposed micro-spade connectors on the standard switch. I have one of these potted lead switches on my clutch lever and it hasn't given any trouble at all.

How did you attach the leads?

[Guest Nogbad]

How did you attach the leads?

 

The switch comes with about a metre of cable already potted in, all you do is connect it into the loom under the tank by crimping new connector halves onto the right length of switch cable. I intend to replace the brake light switch with the same type if and when it goes home.

[Jim Malm]

Thanks to all who replied regarding this problem. My invesitgation revealed that one of the male spade connectors on the microswitch was broken or very close to being so, as it came off in the female side (ouch!) when I disconnected the leads. I saw the stuff on the replacement switches and also contacted Moto International. MI has an after market replacement in stock for about $10 which I immediately ordered. I'll post a comment on how the thingy goes on.

 

I touched the leads together to see if the brake light would work and it did, so the mystery is solved for now. I'm happy not to have to be looking for the wire connections in the bowels of the bike.

 

Thanks again for the help - this forum is a great resource!

 

Jim

[Guest Gary Cheek]

If you care to save a few $$ in the future you can also source the switches from electronics supply houses.

Mouser Electronics www.mouser.com and Digi-Key www.digikey.com are but two sources. You may find from the large selection there are even better choices than supplied at cycle shops.

[Jim Malm]

Gary-

 

Thanks for the comment and information. It cost me a total of $13.06 for the switch and postage from Moto International. It went on and worked properly without any problem (other than the 10 minutes I spent looking for the small brass nut I dropped). I had it delivered to my door the day after I ordered it and the repair was made the day it arrived - record time in the world of Guzzi repairs. I suspected that the switch was probably a common electrical item, but the odds of finding it in Spokane were not high and I'm not skilled in cross referencing electrical components. In this case I feel the money I spent was was well worth the convenience I got from purchasing the part from a knowledgeable dealer.

 

Jim