Horns & MOT/Plod
 

OK folks, generic bike question, so I thought I'd post here... Apologies to the mods if it should be SV Talk...

I had a fun commute home last night :( which left me thinking about a louder horn (something I should of done a long time ago).

My question for the wise members of the org, is pretty simple. How loud can you go before MOT fail, or breaking the law?

I'm fully aware about the threshold of pain (140dB(A)-135db(A) apparently) and the possible effects of hearing (anything beyond 85dB(A)), but I'm looking to find out if there's anything saying I can't push it to, for example, 140dB(A), obviously other than my ears.

For those who would like to comment on my choice of horn, so long as I can find one small enough, I'm planning on taking a trip to a train wreckers yard, and I'm hoping to pickup something like a 12v desiel train horn at around 120dB(A), possibly the 130dB(A) mark.

there's a thread called 'horn problems' somewhere.

people rate the fiamm twins and I'd recommend the stebl magnum x 2. (139DB)

bit of wiring req but worth it

makes me chuckle everytime I use it :lol: even sounds loud with earplugs in :twisted:

law?, mot?. dunno.can't imagine it's a problem

louder the better

I don't know about MOT regulations, but the problem with really loud horns on a bike is that they tend to be big, which makes fitting them problematic. I'd recommend a Stebel Magnum, which is plenty loud, but small enough to fit on a bike. Halfwits sell them, but if you'd prefer to buy from a bike shop, then try http://www.nippynormans.com/

Yea, I did the search a few months back, and I'm well aware of the wiring dilema now (which frankly, is pish).

wyrdness, I know what you're saying about the size, but the main issue really is the size compressor. There's always places to mount the horns themselves and run a high pressure hose to them, it's just where to mount the compressor.

The systems I'm thinking of mostly use a 215psi compressor, and aren't all that small, most don't even run on 12v (trains are like trucks & use 24v - but even that's no real big issue).

The only real contender in my eyes, as far as real bike horns go, is the Stebel Nautilus (139dB(A)) or Magnums, which both go for £23 on the site you linked. If I can find a working, small enough train horn, I can do the entire job (wiring & everything) for around £10.

A pair of Fiamms still wakes people up.

Yep they are good enough.

The Fiamms are pretty loud, but gives no problems with MOT or plod (unless you wake him up!)

Baph already heard my Fiamms so I guess he wants something really loud! :twisted:

Mike, it's not just the volume I'm looking at, it's also the tone. Imagine the sleepy car driver that pulls out & gets the horn from a desiel train. Most people would think "Sh*t where did that train come from?" pretty instinctively. THAT'S the reaction I'm going for.

Interestingly enough, from research, The Road Traffic Act 1972 specifically states that private vehicles must not be fitted with a gong, bell, siren or two tone horn. How many folks have a two tone setup... come on, admit it :P

I've also emailled my Community Beat Manager to ask their advice (without providing my address, phone number, or specifics about my bike etc). I'll update here with whatever they say :)

Two tone horn that it refers to is the old da da horn as fittited to emegency vehicls, not a dual/twin tone horn.

If you cant get a train horn, look at boat horns. I had one on my car many years ago. Woke the MOT guy up every year.

Boats, hmm. Didn't think of that. Most boats operate on 12v, and I live near a lot of water... And I know a few lads that work for an oceanic geologging company that should be able to point me in the right direction... now just to find out about the sound they give off.

Cheers for that thought Vinney :thumbsup:

EDIT: just had a look at some boat horns, and some of them come with a 3L air tank that I'd need to "hide" on the SV :oops:

see here and scroll down a tad.

I found a video last week on Filecabi of a bloke who put a ferry horn on his car and then drove around hooting at people - made I bloody laugh that did.

I haven't got the link so try googling it, however please note that filecabi does contain some non u-rated and NSFW material :wink:

Just remember that +3db is twice as loud.

So a 118db horn will be twice as loud as a 113db horn.

An airhorn will have a slight delay in immiting sound as opposed to an electomagnetic.

Also boat, lorry and trian horns will be bloody big. They only get that tone because of it.

T'is the size of the horn itself that matters. The only thing that really concerns me is the compressor/air tank needed to run the horn, that's the part I'll have difficulty with.

Thanks to Mike, the horns themselves will be fitted inside the bikini fairing on the front, where he has his FIAMM's.

Still to settle on the technology I'll be using, but at the moment, I'm looking at a mixture of compressed air and electromagnetic, best of both & all ;)

I'd say hook up with someone that's fitted twin FIAMMs and check the tone for yourself. I have proper airhorns on the cage and the MOT man bangs his head on the bonnet when his mate tests the horn. I've heard the FIAMMs in action and they have a nice substantial sound- not high and tinny at all.

I'll second the bit about two-tone horns from the regs. Some trains start on one note and switch to a second. These and the siren type are the illegal ones. Twin electrics or air trumpets create a single continuous tone and are OK.

When I finally get around to it, and bearing in mind that my horn likes to go silent now and again, I'll install the twins. Far easier and certainly man enough for me. Oh yes, and they are "E" marked and so road legal.

You could always try HERE

Cheers

Garry 8)[/url]

I dont know much about horns, but I do know that I'm a lot more 'noticable' on the roads since I took the baffle out of my Scorpion can! It's reasonably docile below 4000 rpm, but starts to growl loudly after that! Hopefully I wont attract the wrong kind of attention.

The horn is pants though. Sounds like something you find in a kids party bag.

Hehe, we've got a train horn on our race wagon - it is damn amusing.

The Stebel website has some example sound clips

http://www.stebel.it/stebel/index2006_1.htm

+3db is twice the sound pressure level, but doesn't sound twice as load to the human ear - that's why they use the dB scale, which is logarithmic to reflect the ear's response.

(yes I'm sad) (Used to be a noise test Engineer for a truck company)

I have just looked at the site independentphoto reccomended. OH MY GOD :D :D :D

I want one now.... :lol: :lol:

baph--The complexity of using air on a bike is hardly worth the problem You will have a tank/compressor which would be quite heavy and air trunking plus the tank is going to be so small it would probably only let you have a very short blast Would it be easier to fit a pair of the already recommended horns with directional trumpets

Mint ! I was honking away for ages ! :lol:
Simple thing please simple minds I guess :lol:

How to wake up the neighbours;

Go to the Stebel website, hook up the laptop to the very loud home cinema system, turn volume up to 11, open windows and start honking! :smt046 I honesetly thought I would wee myself laughing watching next door duck for cover. :lol: :lol: :lol: