|
Forums39
Topics49,921
Posts838,285
Members9,638
| |
Most Online1,063 Jun 14th, 2026
|
|
|
|
Joined: Jun 2019
Posts: 812 Likes: 62
Talk Morgan Regular
|
OP
Talk Morgan Regular
Joined: Jun 2019
Posts: 812 Likes: 62 |
|
|
|
|
|
Joined: Feb 2016
Posts: 8,706 Likes: 416
Needs to Get Out More!
|
Needs to Get Out More!
Joined: Feb 2016
Posts: 8,706 Likes: 416 |
Italian Brevettato twin tone air horns with Golfo and Giannini compressor. Quality horns from around the 70's and used on Ferraris's so your in good company. Far superior to the plastic offerings nowadays.
I think that's a lube point on top of compressor. Do they still work?
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone
|
|
|
|
|
Joined: Jun 2021
Posts: 1,989 Likes: 104
Talk Morgan Enthusiast
|
Talk Morgan Enthusiast
Joined: Jun 2021
Posts: 1,989 Likes: 104 |
I respectfully beg to differ....'brevettato' means patented, and isn't that "Giovannini" ? They also have the large hex nuts on the trumpets, and 6 radial bolts on the diaphragm housing, as used on Fiamm's. ![[Linked Image]](https://www.tm-img.com/images/2022/02/28/1970s-Fiamm.jpg)
Peter 2009 3-litre Roadster "Ivor", royal ivory / green
|
|
|
|
|
Joined: Feb 2016
Posts: 8,706 Likes: 416
Needs to Get Out More!
|
Needs to Get Out More!
Joined: Feb 2016
Posts: 8,706 Likes: 416 |
Apologies, yes I meant to type Dolfi and Giovannini based in Florence Peter  Could the name be a forerunner to Fiamm which may explain their similarity? FIAMM an acronym for Fabbrica Italiana Accumulatori Motocarri Montecchio have been around since 1942 so maybe not. Another of D & G's Boss horns here. ![[Linked Image]](https://assets.catawiki.nl/assets/2016/10/27/8/7/a/87a93f1a-9c87-11e6-8767-086fb8a0970d.jpg)
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone
|
|
|
|
|
Joined: Jun 2019
Posts: 812 Likes: 62
Talk Morgan Regular
|
OP
Talk Morgan Regular
Joined: Jun 2019
Posts: 812 Likes: 62 |
I love this horn. Incredible sound. But now the disk on one of the horns has cracked... possibly my fault. It is .005" thick. I ordered some copper and will try to make a replacement. Are there parts available for these? ![[Linked Image]](https://tm-img.com/images/2022/03/01/PXL_20220226_183352495.jpg)
|
|
|
|
|
Joined: Feb 2016
Posts: 8,706 Likes: 416
Needs to Get Out More!
|
Needs to Get Out More!
Joined: Feb 2016
Posts: 8,706 Likes: 416 |
Likely rocking horse poop Paul. The image I posted above of Boss one was from an auction site and historical sale. Very little other info on this brand on the net. Sounds like you have the means of repairing yours though, and a well worth exercise by the sound  of it. Having repaired many vintage horns over the years (although few air ones), I will add that thickness and material of horn diaphragm are critical to sound made, so you will need to experiment. The last one I worked on was a hunting horn with modern driver tested with low pressure air line.
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone
|
|
|
|
|
Joined: Jun 2019
Posts: 812 Likes: 62
Talk Morgan Regular
|
OP
Talk Morgan Regular
Joined: Jun 2019
Posts: 812 Likes: 62 |
Yes, rocking horse poop.
I'm not sure the material that the disc is made from. I'll try copper. Does brass come that thin?
I need to do some homework.
|
|
|
|
|
Joined: Oct 2019
Posts: 5,609 Likes: 618
Charter Member
|
Charter Member
Joined: Oct 2019
Posts: 5,609 Likes: 618 |
If you have a pal with a wood lathe they could turn up a male and female former in half an hour using your old one as a template.... thin copper sheet, well annealed, put between and then the lot smacked with a mallet might replicate your disc.
Whether copper will give a 'bright' enough tone I don't know ... have you tried a magnet on it to give a clue what it's made of?
K
|
|
|
|
|
Joined: Jun 2019
Posts: 812 Likes: 62
Talk Morgan Regular
|
OP
Talk Morgan Regular
Joined: Jun 2019
Posts: 812 Likes: 62 |
No. I hadn't thought of that.
The body of the the horn has that ring formed into it. I'm thinking I might be able to use it as the form. Especially it I heat the copper first.
All I can do is try.
Do you know if modern horns work the same way, possibly having a similar part?
|
|
|
|
|
Joined: Feb 2016
Posts: 8,706 Likes: 416
Needs to Get Out More!
|
Needs to Get Out More!
Joined: Feb 2016
Posts: 8,706 Likes: 416 |
Modern air horns use thin plastic diaphragms. The awoogah/klaxon type use thin spring steel with hardened steel striker rivet. Some material in between I guess but as near to OE as possible.
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone
|
|
|
|
|