So what to do with a duff Commando horn?

Flatspot

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We all know just how %&*£ing awkward it is to get at the non-working Commando horn, but I decided it was a job that needed doing, and while I was at it change my oil hoses to herringbone ones.

I‘ve got it off and bench-tested it and it will not work. It is no more, it’s an ex-horn and not really any use as a paperweight. However, I’ve seen those YouTube videos of people who know what they’re doing taking dead things apart and bringing them back to life. so how difficult can it be?

Let’s have a look inside, and if I destroy it there’s nothing lost. First of all I drilled out, ground down and knocked through the 6 rivets holding it all together. It is well and truly corroded inside and date stamped 1973 when put together by someone in Lucas. 50 years old, it’s not fared too badly.

I wire brushed off all the crap, sanded down the points inside, and then reassembled it, holding it together with a g-clamp. When I added some volts it helped back at me loud and clear. Partial success then!

I then reassembled it fully, reusing the 2 paper gaskets (cheapskate moi) and a dab of 3bond to keep the moisture out. I was able to use some very small nuts, bolts and washers from a “well that’ll be useful let me buy it“ pack of assorted fasteners that have previously been absolutely no use at all. They were a bit long but easily sorted with the Dremel.

I tried it once more now it’s fully back together and it works, and extremely loud it is too!

No one will ever see it again, but I’ve slapped a splosh of primer on it, and I’ll add some gloss black once that’s dried.

That‘s saved me some money, and I’m feeling dead chuffed that it works once more
So what to do with a duff Commando horn?
So what to do with a duff Commando horn?
So what to do with a duff Commando horn?
So what to do with a duff Commando horn?
So what to do with a duff Commando horn?
So what to do with a duff Commando horn?
 
We all know just how %&*£ing awkward it is to get at the non-working Commando horn, but I decided it was a job that needed doing, and while I was at it change my oil hoses to herringbone ones.

I‘ve got it off and bench-tested it and it will not work. It is no more, it’s an ex-horn and not really any use as a paperweight. However, I’ve seen those YouTube videos of people who know what they’re doing taking dead things apart and bringing them back to life. so how difficult can it be?

Let’s have a look inside, and if I destroy it there’s nothing lost. First of all I drilled out, ground down and knocked through the 6 rivets holding it all together. It is well and truly corroded inside and date stamped 1973 when put together by someone in Lucas. 50 years old, it’s not fared too badly.

I wire brushed off all the crap, sanded down the points inside, and then reassembled it, holding it together with a g-clamp. When I added some volts it helped back at me loud and clear. Partial success then!

I then reassembled it fully, reusing the 2 paper gaskets (cheapskate moi) and a dab of 3bond to keep the moisture out. I was able to use some very small nuts, bolts and washers from a “well that’ll be useful let me buy it“ pack of assorted fasteners that have previously been absolutely no use at all. They were a bit long but easily sorted with the Dremel.

I tried it once more now it’s fully back together and it works, and extremely loud it is too!

No one will ever see it again, but I’ve slapped a splosh of primer on it, and I’ll add some gloss black once that’s dried.

That‘s saved me some money, and I’m feeling dead chuffed that it works once more View attachment 105571View attachment 105572View attachment 105573View attachment 105574View attachment 105575View attachment 105576
I've got two here, just might have a go at copying you :)
 
I did the same thing to one last year, sounds as good as the one on my regular Commando. Worth the effort, and nothing to lose by giving it a try!
 
Nice write up. My favorite line.
I was able to use some very small nuts, bolts and washers from a “well that’ll be useful let me buy it“ pack of assorted fasteners that have previously been absolutely no use at all.
I think you have motivated several to get after it...
Well done..
 
Nice write up. My favorite line.
I was able to use some very small nuts, bolts and washers from a “well that’ll be useful let me buy it“ pack of assorted fasteners that have previously been absolutely no use at all.
I think you have motivated several to get after it...
Well done..
And I’ll bet you have something similar in the garage that never gets used - but one day……… ;)
 
This is great for me as mine did not work when I bought the bike in 2018. I chucked it in a box and installed a $15 generic horn which is now pretty useless also. Thanks to this post I will be 'going in' to the original horn in the coming days. Thanks to Flatspot for posting. The pics are just what we needed.
 
When I first got my bike 5yrs ago, the horn seemed dead. After going through other issues the bike had and getting ready for first road tests, went about removing and replacing with Fiamm FreewayBlaster which works very well from same location.

One day I came across the original horn in my growing pile of commando detritus. Had a nearby battery so just did a hook up and HONK!!!! Stinking loud! So turns out the whole issue was the old battery in the bike, which I'd renewed as part of other work done. Didn't have the fortitude to return it to service. Boat anchor-ish weight, effort to install and fact the FB was working so well are my rationalizations.
 
I rebuilt mine the same way Flatspot completed his. This horn is very loud when setup correctly.
They are heavy though.
Flatspot clean your spades before you wire up the terminals. I would use locktite to hold the central bolt as they tend to loosen up from vibration. Once the fender is back in place it is hard to get at. Tell me how I know.:rolleyes:
good job.
 
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Yup, that horn is heavy.
Everyone moans about where it is.
Think about it, it's mounted right in the Center, where weight wise, it does the least harm.
Maybe the Norton guys knew a little a bit about what they were doing..
 
My friend just finished rebuilding his stock horn like Flatspot.Only difference was that he drilled and tapped the holes where the rivets were and used some small screws instead.The horn now works beautifully and is quite loud.After hearing it, I immediately got mine back from the attic to rebuild.
Mike
 
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