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 even sounds loud with earplugs in

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.

[Viney]

A pair of Fiamms still wakes people up.

[TSM]

Originally Posted by Viney

A pair of Fiamms still wakes people up.

Yep they are good enough.

[Luckypants]

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!

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

[Viney]

Originally Posted by Baph

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.

Originally Posted by Viney

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

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