Horn at idle

[Dreamer]

Recently I was caught in a situation whereby I needed to sound the horn to attract the attention of the car reversing in front of me but since the engine was on idling the horn did not function as desired. What modification do I need to make for the horn to work as it should especially in these circumstances. The size of our trikes could easily be missed from the mirrors of the vehicle in front.
Suggestions are appreciated

[mplayle]

Ideally, the horn should work anytime the ignition is turned on, regardless if the engine is actually running or not.

It should have power from an ignition switched source through the horn button to a relay and from the relay to the actual horn. A standard 4-pin relay should be sufficient. Using the relay keeps the current through the horn button lower.

[peakrock]

If you're using the steering column horn push you definitely want it through a relay as the wiring is really thin and won't pass a lot of current. On my Trikings, I installed an 80 amp relay operated by the ignition switch. The switched feed was wired to the starter motor connection which is directly from the battery, This then went to a fused distribution board, like this.

https://www.carbuilder.com/products/led ... e-fuse-box

It comes in four and six way connections and gives you an easy way of wiring power to the horn relay, lights, wiper motor etc.

[Dreamer]

Thank you for your comments. What I failed to add is that the reading on the voltmeter whilst on idle does not exceed 12v at 800rpm. I am using the harness of the motorcycle and the horn is on a relay. What voltage reading do you get on idling?

[mplayle]

I had problems with mine not producing sufficient voltages as well. It turned out to be a poor connection between the alternator and the voltage regulator. When I was researching how to troubleshoot mine, I found a source that said the voltage regulator should be outputing between 13.5 and 14.5 volts. It will swing to the higher side at higher revs.

Once I found the poor connection and fixed it I was always getting at least 13.5 volts, even at idle.

Your battery, by itself, should put out Bout 12.5 volts when fully charged. If your voltage regulator/charging system is not exceeding that, your battery will not properly recharge and eventually run down. That was what happened to mine.

If your charging system is putting out higher voltage when runnign above idle and the horn works, then the 12 volts at idle may not be enough to activate your horn properly.

Attached is a pdf print of the pages from the manual I found online for checking your charging system.