• NOTICE: Starting March 24, we are shifting a user Account upgrade (donation) to post here. Once you've created an account, see the SITE SUPPORT section at the bottom on how to upgrade. This is to help try and cover site costs, and reduce redundant and argumentative posts. Search, read, before staring a new thread. We will still require ONE post in the Intro section to introduce yourself (NO QUESTIONS - THEY WILL BE DELETED). Small $ donations via our link above will not be considered. Also to NOTE, the owner here lost his home in the LA Wildfire storm in January; See the USA section for more details. Your compassion and understanding on use of this site is expected, it is NOT a free social media platform.

brake light flicker - front brake lever play

P

pswiatki

Tuned and Synch'ed
Joined
Aug 26, 2011
Messages
96
Reaction score
20
Location
Wrocław, POLSKA
I noticed my brake light flicker and was able to find the cause: front brake lever has just a bit too much free play and when I ride fast enough (on a highway, above 115-120 km/h - just above 70 mph) the wind pushes the lever enough for the microswitch to activate. Since there is no adjustment on the microswitch itself and it is mounted at a fixed position relative to the lever - how can this problem be addressed? Can I reduce the free play on the lever (so that the lever would not move enough for the switch to activate) or I risk that front brake could engage without my action on the lever? Perhaps it is just the matter of a worn switch that needs replacement? Has anyone experienced a similar problem?
 
You could try mounting the switch further away from the lever. You might have to get a little creative with the mounting arrangement. Try leaving the screws out, and securely fasten it in the new further away position with some good tape. Worth a try.

Edit: If that's too hard, replace it.
 
Thanks for your suggestion. However, this is a safety-critical part. If the tape failed and the switch did not activate I could be rear-ended in a much different way than last time (when I had the opportunity to test my freshly installed engine guards from Hepco&Becker - but it wasn't my stoplight that caused it). So, I shall check how I can move the switch and still have it securely screwed in.
By the way: I taped over the microswitch on the other side (clutch) because it came apart somehow. The tape was really good (TESA tape, a kind of silver duct tape) but that was good only for a season, or so. I guess it deteriorated on the rain and high winds. Still [sort of] holds the switch together, but I will have to replace the switch, I think. Perhaps I should also try a new switch for the brake.
 
Last edited:
You could cover your "safety-critical" issue by operating your rear brake in conjunction with the front, lightly if desired.

But your lack of an operating clutch switch is also a safety issue. Replace both would be a good starting point.
 
I would replace the clutch and brake switch. As the number of duct tape repairs begins to build, soon the bike becomes unreliable and dangerous. A few small repairs at a time is less overwhelming than a huge and expensive list all at once.
 
Raven said:
I would replace the clutch and brake switch. As the number of duct tape repairs begins to build, soon the bike becomes unreliable and dangerous. A few small repairs at a time is less overwhelming than a huge and expensive list all at once.
Click to expand...

True, I fully agree - with one remark: I think the clutch microswitch is less of a problem, as it can only become a pain when the clutch is actually disengaged, but the cluster / ECU doesn't get the confirmation from the switch. Then it will refuse to start the engine when the gearbox is in gear. Am I right? That is: unlike the front brake microswitch (which is a safety concern) the clutch microswitch is less critical. Hmm... although I can imagine the situation where the engine stalls and must be restarted quickly (no time to put in neutral, just to pull the clutch lever) - that would be an issue...
Anyhow, I shall order the switches and put them on the bike.

By the way: had the flicker on the stoplight mounted in the GIVI top case - it was always present (at low speed, too) - turned out to be a bad assembly inside one of their fancy touch-connectors at the case to mount plate touchpoint. At least that one was easy to address.
 
pswiatki said:
I noticed my brake light flicker and was able to find the cause: front brake lever has just a bit too much free play and when I ride fast enough (on a highway, above 115-120 km/h - just above 70 mph) the wind pushes the lever enough for the microswitch to activate. Since there is no adjustment on the microswitch itself and it is mounted at a fixed position relative to the lever - how can this problem be addressed? Can I reduce the free play on the lever (so that the lever would not move enough for the switch to activate) or I risk that front brake could engage without my action on the lever? Perhaps it is just the matter of a worn switch that needs replacement? Has anyone experienced a similar problem?
Click to expand...

On my '14 Stelvio there is a plunger type switch that touches the brake lever. I can wiggle it and get the light to stay on. Everyone has told me replace the small microswitch that has the spade connectors, that appears to be a separate part? Maybe yours has a similar part/switch?
 
Well, I will take a picture of the switch and post it here. I guess the best option, for now, is to get a new switch and try if it helps.
 
Had the exact same issue with brake light flickering. Rather than try and super glue a bit of plastic on the front brake lever as Robert did, a bit of 6mm fish tank hose works just as well (and I can't see it coming off in a hurry)
 

Attachments

  • P1030648.webp
    P1030648.webp
    23.4 KB · Views: 15
  • P1030649.webp
    P1030649.webp
    40.3 KB · Views: 13
pswiatki said:
I noticed my brake light flicker and was able to find the cause: front brake lever has just a bit too much free play and when I ride fast enough (on a highway, above 115-120 km/h - just above 70 mph) the wind pushes the lever enough for the microswitch to activate. Since there is no adjustment on the microswitch itself and it is mounted at a fixed position relative to the lever - how can this problem be addressed? Can I reduce the free play on the lever (so that the lever would not move enough for the switch to activate) or I risk that front brake could engage without my action on the lever? Perhaps it is just the matter of a worn switch that needs replacement? Has anyone experienced a similar problem?
Click to expand...
I do have a similar problem - a friend riding behind me on my '09 Stelvio noted that at highway speeds, my brake light flickers on/off when I'm cruising.

The front brake lever has the right free play for operating the brake, and the switch is operating reliably when touched by the lever. However, there is NO "free play" in the switch and no way to adjust the gap between the lever and the switch (that I can see), so that the brake light will operate when I squeeze the lever, but will NOT come on when the wind at 65 mph moves the lever back a millimeter or so, operating the switch when I don't want it to.

I also found this on the subject:

I discovered this weekend that my front brake light switch was set-up to be too sensitive.

From years of curvy road riding, I habitually ride with one or two fingers covering my brake lever so as to have quicker response when I need to scrub-off some speed. A chap behind me during a ride on Saturday commented that sometimes he could see my brake light just barely come on and flicker. Close inspection revealed that any finger contact with the brake lever would click the microswitch and turn-on the brake light way before the master cylinder was engaged.

I discovered that virtually no adjustment of the switch can be made by loosening the screw that holds it and repositioning. I ended up cutting a very small piece of .020 brass shim stock and attaching it to the contact point on the lever with some silicone RTV to create even more contact with the switch button.

My problem is fixed and now the light comes on only when the lever is pulled back beyond the slack.

I don't understand how adding a shim to the lever will help this problem. It seems to me that it will activate the switch even earlier, which I don't want. Before I start taking things apart, will I find that the position of the switch relative to the brake lever is adjustable once I disassemble it? Perhaps I don't understand the relationship between the actuator and the switch on the M/C.

Thanks!

Lannis
 
Last edited:
Lannis said:
I do have a similar problem - a friend riding behind me on my '09 Stelvio noted that at highway speeds, my brake light flickers on/off when I'm cruising.

The front brake lever has the right free play for operating the brake, and the switch is operating reliably when touched by the lever. However, there is NO "free play" in the switch and no way to adjust the gap between the lever and the switch (that I can see), so that the brake light will operate when I squeeze the lever, but will NOT come on when the wind at 65 mph moves the lever back a millimeter or so, operating the switch when I don't want it to.

I also found this on the subject:

I discovered this weekend that my front brake light switch was set-up to be too sensitive.

From years of curvy road riding, I habitually ride with one or two fingers covering my brake lever so as to have quicker response when I need to scrub-off some speed. A chap behind me during a ride on Saturday commented that sometimes he could see my brake light just barely come on and flicker. Close inspection revealed that any finger contact with the brake lever would click the microswitch and turn-on the brake light way before the master cylinder was engaged.

I discovered that virtually no adjustment of the switch can be made by loosening the screw that holds it and repositioning. I ended up cutting a very small piece of .020 brass shim stock and attaching it to the contact point on the lever with some silicone RTV to create even more contact with the switch button.

My problem is fixed and now the light comes on only when the lever is pulled back beyond the slack.

I don't understand how adding a shim to the lever will help this problem. It seems to me that it will activate the switch even earlier, which I don't want. Before I start taking things apart, will I find that the position of the switch relative to the brake lever is adjustable once I disassemble it? Perhaps I don't understand the relationship between the actuator and the switch on the M/C.

Thanks!

Lannis
Click to expand...
Most contact brake light light switches are push to break type. That is the circuit is open when the plunger is pressed in. Adding that shim keeps the plunger pressed in so it doesn't complete the circuit.
 
You must log in or register to reply here.
Back
Top