rear brake
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Joined: Mar 2010
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From: Honah Lee
I have connected the two wires coming from the hydraulic banjo bolt, to the multimeter, then pressed the pedal. Nothing happened. Means the switch from the bolt doesn't close.
But when I remove the hydraulic banjo bolt, connect it, again, to the multimeter and push inside it with an thin allen key, the switch closed (as in the picture).
Maybe not enough pressure in the system, or some air bubbles inside the hydraulic switch, I notice the hole inside of it is quite deep.. air can be trapped there... just thinking
But when I remove the hydraulic banjo bolt, connect it, again, to the multimeter and push inside it with an thin allen key, the switch closed (as in the picture).
Maybe not enough pressure in the system, or some air bubbles inside the hydraulic switch, I notice the hole inside of it is quite deep.. air can be trapped there... just thinking
Somehow, I have yet to hear you say pressing with the allen made the rear light work.
Last one I installed, screw type, I quickly screwed it in a few turns leaving it loose. I lightly applied brake pressure letting fluid drip out.
Try elvating it bike. I once broke a bleeder off. I just pulled the caliper and with it angled correctly, and a block between pads, blead it with the banjo fitting.
Lot of people have trouble bleeding front brake from putting bars In wrong position.
Last edited by Jackie Paper; Dec 20, 2025 at 12:55 PM.
Air compresses, unlike brake fluid, air may be the issue.
Somehow, I have yet to hear you say pressing with the allen made the rear light work.
Last one I installed, screw type, I quickly screwed it in a few turns leaving it loose. I lightly applied brake pressure letting fluid drip out.
Try elvating it bike. I once broke a bleeder off. I just pulled the caliper and with it angled correctly, and a block between pads, blead it with the banjo fitting.
Lot of people have trouble bleeding front brake from putting bars In wrong position.
Somehow, I have yet to hear you say pressing with the allen made the rear light work.
Last one I installed, screw type, I quickly screwed it in a few turns leaving it loose. I lightly applied brake pressure letting fluid drip out.
Try elvating it bike. I once broke a bleeder off. I just pulled the caliper and with it angled correctly, and a block between pads, blead it with the banjo fitting.
Lot of people have trouble bleeding front brake from putting bars In wrong position.
I also loosened the damn screw and let the fluid drip out, but did not help.
I will try tomorrow to elevate the front of the bike, to make it easier for the air to escape.
By one side, I think there is air inside the bolt, which makes the switch not to work. But, then, I do not understand why the pedal is so firm when pressed.
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Joined: Jun 2012
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From: CT/FL
I'm not trying to be rude, but you've proven the switch works, but not that the bike wiring is good. It's a simple thing to touch the bike wires together with the key on and check it out.
I did that, in the beginning, the light & wiring is working well.
Seasoned HDF Member
Joined: Mar 2010
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From: Honah Lee
When I push with the allen, the switch close, I have checked with the multimeter, means the rear light will work. So, I assume the hydraulic banjo bolt switch is ok.
I also loosened the damn screw and let the fluid drip out, but did not help.
I will try tomorrow to elevate the front of the bike, to make it easier for the air to escape.
By one side, I think there is air inside the bolt, which makes the switch not to work. But, then, I do not understand why the pedal is so firm when pressed.
I also loosened the damn screw and let the fluid drip out, but did not help.
I will try tomorrow to elevate the front of the bike, to make it easier for the air to escape.
By one side, I think there is air inside the bolt, which makes the switch not to work. But, then, I do not understand why the pedal is so firm when pressed.
Always after any brake work and bleeding, hold a firm pressure as hard as you brake for one minute. Pedal or lever should not drop.
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Joined: Mar 2010
Posts: 21,100
Likes: 7,629
From: Poolville
You obviously have an air bubble in the switch. I've never used that style switch but have had an air bubble at the stock switch on my softail and if you step really hard on the brake pedal "REAL HARD" it will come on.. Seeing that the switch is beyond the brake line it's very possible the air is not coming out.. Creating a better angle to the bike allowing the banjo bolt to be the lowest part in the system (compared to the master cylinder and brake line) might help.. I would pump the pedal lightly when the bike is at angle to help assist in removing the air.. Maybe even tap gently on the banjo bolt and do it with the cap off the reservoir..
Merry Christmas....
Merry Christmas....
You obviously have an air bubble in the switch. I've never used that style switch but have had an air bubble at the stock switch on my softail and if you step really hard on the brake pedal "REAL HARD" it will come on.. Seeing that the switch is beyond the brake line it's very possible the air is not coming out.. Creating a better angle to the bike allowing the banjo bolt to be the lowest part in the system (compared to the master cylinder and brake line) might help.. I would pump the pedal lightly when the bike is at angle to help assist in removing the air.. Maybe even tap gently on the banjo bolt and do it with the cap off the reservoir..
Merry Christmas....
Merry Christmas....
This is exactly what I suspect, a small air bubble into the hydraulic banjo bolt switch.
Small enough to allow the brake system to perform well, but big enough that the switch doesn't work.
I lifted the front of the bike, maybe 45 degrees, so that the air can escape easier from the inside of the bolt, primed the installation, but no results. Pressed hard on the brake, almost to bend the pedal bracket, no results.
I ordered a new banjo bolt switch, from a different company, maybe it has a different internal architecture and can be primed easier. But, if no succes, I will install a mechanical switch, and replace the hydraulic bolt. I cannot go back to stock because this is a custom project.
Thanks
Marcel
Last edited by marcelm; Dec 26, 2025 at 03:37 AM.
Seasoned HDF Member
Joined: Jun 2012
Posts: 6,154
Likes: 2,562
From: CT/FL
Have you tried removing the whole caliper with the hose attached and moving it so the switch can release its bubble? Let it set overnight
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From: poway
If you can generate enough pressure to activate the brakes you will generate enough pressure to activate the switch. Pressure inside a closed system be liquid or air is the same throughout the system. The switch is defective. Simply pushing a rod into the switch simply mean that contacts are good. The disc that is inside the switch lost it's seal.
Seasoned HDF Member
Joined: Mar 2010
Posts: 21,100
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From: Poolville
If you can generate enough pressure to activate the brakes you will generate enough pressure to activate the switch. Pressure inside a closed system be liquid or air is the same throughout the system. The switch is defective. Simply pushing a rod into the switch simply mean that contacts are good. The disc that is inside the switch lost it's seal.
Last edited by 98hotrodfatboy; Dec 27, 2025 at 12:08 PM.