I've gotten a little tired of red light runners, and intersection
blockers and it's getting worse and worse as traffic increases in my
area. I decided that it was time for a louder horn on my
"transportational" bike.
I got a 12 volt compact air horn <
http://www.amazon.com/dp/B000F5DQWY>
and a 14.8V Li-Ion battery pack <
http://www.ebay.com/itm/131590167806>.
The handlebar switch has not yet arrived
<
http://www.ebay.com/itm/311504686111> but everything else is in place.
Harbor Freight has the horns for a little less (with their 20% off coupon).
It all fits under my Porteur Rack <
http://oi63.tinypic.com/f4fqd4.jpg>.
The battery, fuse holder with 15A fuse, and horn relay, fit in a shallow
4" square electrical box.