Faulty horn - how can I repair it?

[Fuzzy]

Hi guys, I have a twin horn set-up on my Fzs600 and I noticed that one of them had stopped working. They are Piaa sports horns like these:

http://www.demon-tweeks.co.uk/Product.do?method=view&n=1968&g=246643&p=379841&c=215&utm_source=Google&utm_medium=Base&utm_campaign=Horns&gclid=CLf1kPDdlLwCFWITwwodzjwAEQ


Been on the bike a year or so and wired in with a relay. I replaced the one that stopped working with the oem horn and that works fine so it is not a problem with the bike's wiring, it is a problem with the horn itself.

I would like to repair it as the horns were damn good at waking up dozy peds & cagers on my commute through London, but I'm crap at electrics. Anybody know what to look for when it comes to broken horns?

Thanks

[Fazerider]

If you can get it open in a non-destructive manner, then you'll understand how it works pretty well immediately.
The current flows round the solenoid creating a magnetic field which pulls the iron core. That is attached to the diaphragm and the contact breaker. Once it's reached a certain point the contact breaker cuts the supply to the coil, the diaphragm springs back until contact is made again.


There are several things that can go wrong:
The contact points can get dirty in which case a bit of emery paper and contact cleaner will do the trick.
The separation point of the contacts is quite critical, you may need to dig some sealant away first, but there should be an adjustment screw there.
Less easy things to fix would be a burnt out coil, or (what usually happens to old horns) the rim of the diaphragm rusts away until it can't provide the springiness needed for the return half of the noise-making cycle.

[Fuzzy]

Many thanks for the reply, the unit seems in fairly good order and I cannot imagine there will be a lot of rust inside so I think I'll start with the adjustment screw. I fiddled with it earlier to no avail but will be more thorough with it tomorrow.

[Grahamm]

[Insert V!agra joke here]