Author Topic: Brake light stays on  (Read 4410 times)

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ateamsam

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Brake light stays on
« on: July 13, 2009, 08:26:30 AM »
Hey Guys,

My brake light on my 550 simply just stays on.  I can't seem to find a thread about this and was wondering if anyone could point me in the right direction.
-Thanks,
Sam

Offline Laminar

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Re: Brake light stays on
« Reply #1 on: July 13, 2009, 08:29:03 AM »
The brake light is activated in two possible ways:
1. A pressure-activated switch attached to your front brake light, usually mounted on the lower triple-tree mount.
2. A linear switch attached via a spring to your rear brake pedal.

I'd look at the rear brake switch first and make sure that it's adjusted correctly. You can adjust a nut on the switch body to set the tension in the spring and decide where the switch is activated and the light is turned on. If that's fine, I'd look at the wiring and make sure everything is hooked up correctly.

Did this issue pop up recently or has it been going on for a long time?

Offline Inigo Montoya

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Re: Brake light stays on
« Reply #2 on: July 13, 2009, 08:40:12 AM »
My 750 did this. If I used the rear, it would stay on. Turns out the switch was dry. It needed a bit of lube and it worked fine. As the pedal goes down, it pulls on a spring and then on a switch that pulls out. This switch has a spring on the inside to move it back in. I used a drop of light oil(maybe not the best) and worked it around a bit and it was fine after that. best part is it didnt cost anything! ;)

ateamsam

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Re: Brake light stays on
« Reply #3 on: July 13, 2009, 01:23:31 PM »
Thanks for the tips guys.  i just bought the bike so its a pre-existing issue that I only just noticed.  As soon as I get home I'll have to do some more investigating
-Sam

Offline flybox1

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Re: Brake light stays on
« Reply #4 on: July 13, 2009, 01:41:10 PM »
my 350F did this when i adjusted the rear pedal to fit my foot position.  the rear linear switch needed to be adjusted for the new pedal position.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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ateamsam

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Re: Brake light stays on
« Reply #5 on: July 13, 2009, 09:06:12 PM »
THE SWITCH WAS TOO TIGHT!!! talk about a simple fix.  Thanks for all the help guys.

Offline Laminar

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Re: Brake light stays on
« Reply #6 on: July 13, 2009, 09:15:35 PM »
THE SWITCH WAS TOO TIGHT!!! talk about a simple fix.  Thanks for all the help guys.

Awesome. Gotta love the easy fixes.

Offline Inigo Montoya

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Re: Brake light stays on
« Reply #7 on: July 14, 2009, 06:45:20 AM »
Especially when they are free!

Offline NShahdadi

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Re: Brake light stays on
« Reply #8 on: November 04, 2012, 09:38:52 AM »
Just had the same problem. Screw was too tight. The forum saves the day (and the wallet) again!
1976 CB550K

Offline Stev-o

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Re: Brake light stays on
« Reply #9 on: November 04, 2012, 11:24:05 AM »
Recently repaired mine too. 
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 76cb550k

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Re: Brake light stays on
« Reply #10 on: March 28, 2013, 12:51:50 AM »
Just had the same problem. Screw was too tight. The forum saves the day (and the wallet) again!
can you explain where the screw was that you adjusted?


Offline NShahdadi

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Re: Brake light stays on
« Reply #11 on: March 28, 2013, 06:25:35 AM »

can you explain where the screw was that you adjusted?
[/quote]

http://www.bikebandit.com/houseofmotorcycles/1976-honda-cb550k-exhaust-muffler-step-step/o/m9447sch399665

I think it's 38/48 on that diagram. It's basically a bolt that adjusts your brake lever return, if I recall. Just start tinkering with it and you'll see exactly how it works, it's real simple. Turn your power on so you know when your brake light goes on/off.
1976 CB550K

Offline Stev-o

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Re: Brake light stays on
« Reply #12 on: March 29, 2013, 11:29:01 AM »
Just had the same problem. Screw was too tight. The forum saves the day (and the wallet) again!
can you explain where the screw was that you adjusted?


Front or rear brake? If rear, did you check the switch? It's connected to the pedal by a spring.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 76cb550k

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Re: Brake light stays on
« Reply #13 on: March 31, 2013, 03:44:02 AM »
the weird part is all i did was fiddle with the exhaust to try to make it sit better and try to tighten the right hand brake lever (i didnt' actually do anything).

lastly, i removed the ignition to get some new keys recut.

all-in-all, i didn't do anything near the brake equipment and it seems to have caused the brake light to stay on.

i will try to loosen the nuts and see what happens.  can you tell me where the front hand brake adjustment is?

Offline dave500

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Re: Brake light stays on
« Reply #14 on: March 31, 2013, 04:44:51 AM »
a cop pulled me over the other day,,he told me my brake light isnt working,,i just said thats ok,,im not stopping!

Offline SohRon

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Re: Brake light stays on
« Reply #15 on: March 31, 2013, 08:36:46 AM »
Do your rear brake pedal adjustment first; once it's correctly adjusted then set the rear switch. Look at your Owner's manual or Shop Manual for the settings.

The front switch is non-adjustable; you either have pressure or you don't. Is your front caliper free and releasing properly? If the caliper sticks, the internal pressure can keep the switch activated...

The closest thing to an adjustment that's available on the MC end is the little rubber stop that fits into the small hole near the lever bolt on the underside of the MC... if it's missing the lever will flop around and seem to be out of adjustment...
« Last Edit: March 31, 2013, 08:39:51 AM by SohRon »
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Assembling my '74 CB550: http://forums.sohc4.net/index.php?topic=86697.0
Assembly of the Right-hand Switch (a rebuilder's guide):  http://forums.sohc4.net/index.php?topic=80532.0
Installing stock 4X4 exhaust: CB500-CB550 K: http://forums.sohc4.net/index.php?topic=82323.0
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Offline crobar

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Re: Brake light stays on
« Reply #16 on: May 08, 2018, 05:42:33 AM »
I'm having the same problem with the brake light staying on. I disconnected the front switch(pulled the terminals from the switch) and it still stayed on. That tells me it must be the rear switch, right?

I have done some adjustment to the rear brake lever and the switch but it is still staying on. I'm thinking that means it's time for a new switch. Sound right?

Offline evanphi

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Re: Brake light stays on
« Reply #17 on: May 08, 2018, 07:15:07 AM »
I'm having the same problem with the brake light staying on. I disconnected the front switch(pulled the terminals from the switch) and it still stayed on. That tells me it must be the rear switch, right?

I have done some adjustment to the rear brake lever and the switch but it is still staying on. I'm thinking that means it's time for a new switch. Sound right?

Try unhooking the spring from the brake pedal. If the light goes out it jut needs to be adjusted. If it still stays on then it may need to be lubed a bit, or replaced.
--Evan

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Offline flybox1

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Re: Brake light stays on
« Reply #18 on: May 08, 2018, 09:40:05 AM »
The rear switch unit is held in a mount, with two nuts, one above and one below the mount.  loosen the top one of these slowly until the brake light goes out, and then go one turn looser.  Leave the top nut where it is.  Now, snug up the bottom one up to the mount....securing the unit in its new location.
Done
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline PeWe

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Re: Brake light stays on
« Reply #19 on: May 08, 2018, 10:57:15 AM »
That was the fix when rear light burned, adjust the brake light switch that is threaded in its holder until brake light is constantly on. Then possible to ride in the dark night...
Opposite, adjust it the other way, spring to pedal need some slack
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
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http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline crobar

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Re: Brake light stays on
« Reply #20 on: May 09, 2018, 06:08:20 AM »
It was the rear switch, and it only needed adjustment, switch is still good. Thanks all.