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Vehicle: Bicycle: Wheel
Civil Defense Bicycle Hub   (+13)  [vote for, against]
Hub Mounted Mechanical Siren

The front wheel hub of my bicycle is a bit lazy. The rear one is OK, it's got a nifty epicyclic gearbox in it, which is nice. So I want to put the front to better use, I'd say that a dynamo would be a good idea, but it's already been done.

So, an old style mechanical air-raid type siren is effectively a centrifugal fan, with slotted exits. There's often a bit of a horn-style motif to improve the whole direction of the sound control thing. We could use an epicyclic gearbox in the front hub to power such a siren. A cable operated clutch would bring it in and out of operation, otherwise you'd have a constitutive Sirencycle*

This machine could be used to ride around areas that need a good siren-ing. Such as nuclear missile targets, tornado zones or France. Alternatively it could just be a jolly feature to have on your bicycle to enjoy with like- minded chums.

* which I think is near Cheltenham.
-- bs0u0155, Aug 20 2014

[xandram], this is as close as I can get Cement_20Truck_20Mu...Ice_20Cream_20Maker
[normzone, Aug 21 2014]

Gears http://sheldonbrown.com/derailer.html
I think Sheldon would have liked the HB [bs0u0155, Aug 21 2014]

Horror of horrors! It has just occurred to me to wonder whether or not the unique sound of bagpipes might be emulated by your bicycle siren.
-- Vernon, Aug 20 2014


You could use it to warn OF imminent bagpipe deployment...
-- bs0u0155, Aug 20 2014


No downside.
-- bungston, Aug 20 2014


Except for lovelorn men chasing after you in the street attracted to your siren song.
-- rcarty, Aug 21 2014


Out of interest, which geared hub are you using, and are you using chain or belt drive? I'm considering upgrading, but I can't get anyone to recommend anything other than a rohloff (at like $2k+).
-- Custardguts, Aug 21 2014


// A cable operated clutch // jammed in engaged position 5 km from home at sunset [+]
-- piluso, Aug 21 2014


+ Can we get an alternate Ice Cream Truck song / siren?
-- xandram, Aug 21 2014


//which geared hub are you using//

A 1966 Sturmey Archer 3 speed, with the original chain. Derailleur systems <link>, with all their wibbly- wobbly compromise cogs, are for the sort of weak minded individuals that buy a set of 107 kitchen knives off late night cable TV.

In all seriousness, I hear the new Sturmey Archer stuff is heavy but good.
-- bs0u0155, Aug 21 2014


I'm pretty sure Sturmey Archer now do a fixed-gear (i.e. no freewheel) 3-speed hub, for the hipsters.
-- hippo, Aug 21 2014


Sturmey Archer is the best. I detest those derrière gear systems. No man or woman needs any more than 3 speeds.
-- xenzag, Aug 21 2014


The Shimano Alfine is available in 8 and 11 speed versions. I've not ridden one but a few people at work ride them. Not sure of the price but definitely cheaper than a Rohloff.
-- EnochLives, Aug 21 2014


[+] idea, [+] piluso's anno.
-- calum, Aug 21 2014


[+] make them mandatory during the French stages of the Tour De France to ensure a bloody good siren-ing.
-- DenholmRicshaw, Aug 21 2014


//mandatory during the French stages of the Tour De France to ensure a bloody good siren-ing//

That would be fantastic, imagine the din of a furiously sirening peloton descending an alp.
-- bs0u0155, Aug 21 2014


Well, if you are going to use this going downhill in France, the sound of a WWII Stuka siren might be a bit much.

If you built it right, you could use the front forks as the siren horns. The shape is vaguely the same.
-- baconbrain, Aug 21 2014


// use ... in France, ... a WWII Stuka siren might be a bit much //

Au contraire, it will just mean the french riders increase their speed to get away ...
-- 8th of 7, Aug 22 2014


// french riders increase their speed to get away ...//

which increases the tone and intensity of the siren, which increases the speed further...

A vicious cycle if you will.
-- bs0u0155, Aug 22 2014


<applause>
-- 8th of 7, Aug 22 2014


<more applause>
-- AusCan531, Aug 22 2014



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