Rear Brake Switch (or owner) Failure

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Just a quick (I think) rear brake switch question:

I've been through a couple of rear brake switches since I got my 72 Roadster in 2017. The first one came with the bike and might have been decades old for all I know. The second one was on for just one full season before it died the same death as the original: the rubber split and the top part of the switch was blown away behind me and into the Commando contrail, leaving me with full and continuous tail illumination until one of the rear switch wires was unplugged.

I'm wondering if the switch failure was my fault. I noticed that someone on here mentioned packing the switch with grease, which I did not do. Is that standard procedure, and would that have kept it alive for years? Is there anything else I can do to keep an original type rear brake switch going for a few years? Or should I just rig up a different switch as many seem to have done?

Thanks!
 

Nater_Potater

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I know some have packed the switch with Vaseline or similar to ward off water intrusion, but that's probably not the trouble here. I doubt it's your fault; rather, poor quality of the replacement switch. My OE from '74 is still going strong. Okay, now I've done it! Soon to fail...
 

Mart UK

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My mk3 switch boot was hanging on, nearly in two pieces, after 4,000 miles. I've replaced it and am hoping to keep it going with red rubber grease on the inside and a film of the same on the outside of the boot. I'm planning to reapply to the outside after each wash, when I remember.
 

ashman

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The original switch lasted over 35 years on my Norton before it fell apart, gone through 2 replacements since as the the newer ones are crap, I have replace my rear brake switch with a old Honda dirt bike switch will never go back to the crappy ones, it was a easy job to replace with a Honda brake switch and works so much better and is well sealed.

Ashley
 

ashman

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Most go for originals for keeping the bike stock, me I go for safety all the time over original, as most time you don't know they have failed or fallen apart while out and about, sometimes you don't know till you get a ticket or someone rear ending you, but then any switch can fail but the Honda ones seem to last forever, mine is off a old 74 Honda dirt bike and spent most of its time in the dirt, mud, dust and of course creek crossings.
 

batrider

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There is an adjustment for brake pedal height for the lever stop and a separate adjustment for the switch travel by moving the switch. Make sure the switch is not getting smashed when the brake is off. Mine lasted nearly 40 years. Now using a large pushbutton microswitch where the original switch mounted. I made a hole adapter plate with a piece of 1/4" aluminum. The switch needs to have normally closed (NC) contacts. The one I found has both normally open and normally closed terminals. I bought 10 nice quality switches from an electronics surplus house and I'm still on the first one.
 

robs ss

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As stated by @ashman above and done eloquently by @cliffa you should think seriously about the Japanese pull-type switch.
Here's the link to his original post (hopefully works?) and below that a photo of my copy of his idea.
Commando folklore

Brake switch.JPG
 
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My original 73 switch finally broke in 2017 . It broke where the wires plug in. So I ordered a new one and installed it, it went about a week before the bellows split.
So I used the bellows from the old switch which was about 3 times the thickness as the new one, and have had no problems since.
 
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I fitted a new AN switch last year and the bellows has split. Clearly it’s not very durable, and the ‘Wassells replacement is from the same factory judging by the moulding marks. it ain’t gonna last long. What a crap method of operation, press to ‘off’ , it’s time to look at a conventional pull switch.
 

maylar

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I guess they don't make 'em like they usta. My first one lasted 35 years, the second has been ok for 10 and counting.
 
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I’ve been tidying up my boxes of spares today, and came across the broken switch I removed last year. One of the 2 bolt holes had broken off, but I kept it anyway.

The rubber on it is perfectly sound and like new, despite being I reckon the original from 47 years ago. Thankfully I’m rewarded by not wanting to throw old useless stuff away.
 
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I sort of did away with my rear brake light switch. When the last one went bad I never replaced it. Even with the so called premium unit, the rubber would still rot away in a couple seasons. I know its only 10 bucks but eliminating any questionable electrical item on a Commando is not a bad thing.
It's so rare that I would use the rear brake on its own, always using the front for primary stopping and rely on its switch for brake lights. I feel subconsciously that the rear is not functional and may come up with a better solution. I would rather not have an "inline" switch.
 

Beach

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There is an adjustment for brake pedal height for the lever stop and a separate adjustment for the switch travel by moving the switch. Make sure the switch is not getting smashed when the brake is off. Mine lasted nearly 40 years.

This I would say is the most common cause for failure of this switch. I also pack switches and connectors with dielectric grease.
 
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There is an adjustment for brake pedal height for the lever stop and a separate adjustment for the switch travel by moving the switch. Make sure the switch is not getting smashed when the brake is off. Mine lasted nearly 40 years. Now using a large pushbutton microswitch where the original switch mounted. I made a hole adapter plate with a piece of 1/4" aluminum. The switch needs to have normally closed (NC) contacts. The one I found has both normally open and normally closed terminals. I bought 10 nice quality switches from an electronics surplus house and I'm still on the first one.
Interesting, thanks!
 
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My original 73 switch finally broke in 2017 . It broke where the wires plug in. So I ordered a new one and installed it, it went about a week before the bellows split.
So I used the bellows from the old switch which was about 3 times the thickness as the new one, and have had no problems since.
Wow - they don't make em like they used to...
 
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I sort of did away with my rear brake light switch. When the last one went bad I never replaced it. Even with the so called premium unit, the rubber would still rot away in a couple seasons. I know its only 10 bucks but eliminating any questionable electrical item on a Commando is not a bad thing.
It's so rare that I would use the rear brake on its own, always using the front for primary stopping and rely on its switch for brake lights. I feel subconsciously that the rear is not functional and may come up with a better solution. I would rather not have an "inline" switch.
I've been doing the same thing so far.
 
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