Bike horn distortion at high speed / rpm

gopaneel · 14th April 2015, 10:49

I own a Honda Unicorn from 2007, the one with spoke wheels. Few years back, I changed the single stock horn to dual Hella Disc horns. The horns are smaller than those on the Pulsar and I really like the way they sound. They are wired with a relay and from what the electrician told me, the horns are isolated from the horn switch and connected directly to the battery.

Right from when the horn was changed, the problem I've faced is that the horn sound gets distorted at high speed. My thoughts are, it is probably due to higher current from the electrical system at high speed. But since it is connected directly to the battery, can a higher current flow through? Also, has anyone had an issue of horn distortion at high RPMs? Finally, how do I resolve the issue?

Mods, even though my query is regarding a bike horn, I'm putting it in the accessories section because there is a chance that car owners have also faced the same issue.

bblost · 14th April 2015, 12:50

My thoughts on this:

While the horn is connected to the battery, the battery is still connected to the alternator.
So the voltage available to horn is going to be whatever is higher at a given moment.

When running high the alternators wires are carrying higher voltage. These same wires are also in contact with the wires that are going to the horns.
They will get distorted at high speeds.

I don't think its possible to isolate them. The only option is getting horns that are able to work with this voltage range.

adrian · 14th April 2015, 13:23

Quote:

Originally Posted by gopaneel

I own a Honda Unicorn from 2007, the one with spoke wheels.

Mods, even though my query is regarding a bike horn, I'm putting it in the accessories section because there is a chance that car owners have also faced the same issue.

Assuming that the horns in question is of a diaphragm type, check the mounting brackets if they are installed properly and the horn itself is not touching nearby metal parts during vibrations at high rpms thereby hindering the proper functioning of the diaphragm.
regards adrian

gopaneel · 14th April 2015, 13:36

Mod Note : Please use the EDIT or MULTI-QUOTE buttons instead of typing one post after another on the SAME THREAD!

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Quote:

Originally Posted by bblost

My thoughts on this:

While the horn is connected to the battery, the battery is still connected to the alternator.
So the voltage available to horn is going to be whatever is higher at a given moment.

When running high the alternators wires are carrying higher voltage. These same wires are also in contact with the wires that are going to the horns.
They will get distorted at high speeds.

I don't think its possible to isolate them. The only option is getting horns that are able to work with this voltage range.

But wouldn't all auto horns be rated at 12V. Also, at higher RPMs would the voltage or current be increasing?

Quote:

Originally Posted by adrian

Assuming that the horns in question is of a diaphragm type, check the mounting brackets if they are installed properly and the horn itself is not touching nearby metal parts during vibrations at high rpms thereby hindering the proper functioning of the diaphragm.
regards adrian

This is something I've never thought of. Even though I assume it's well fitted, I will take a closer look.

rakesh_r · 14th April 2015, 13:51

Put the bike on centre stand and with the bike in Neutral rev the engine and check if the problem exists.Also check the horn clips.Tighten them if they are loose.

Technocrat · 15th April 2015, 18:03

Hmm so the relay is already in place, how old is the battery? Can you try by temporarily putting a new one in place?

Also have you checked to see if the wiring is lose?

Also what do you mean by the horns are isolated fomr horn switch? How do you operate them? via a separate switch?

saket77 · 15th April 2015, 18:11

Hello Gopaneel,

There is an adjustment screw behind the diaphragm of the horn. Use this screw to adjust the tone of the horn and you may hit the right spot. It may be locked by a nut under the screw and may be covered by a tiny rubber housing. You will have to remove the rubber cover to have access to the adjustment screw. Try this procedure and report us back.

Regards,
Saket

girimajiananth · 15th April 2015, 19:32

If you find the horn to be loosely mounted , you may want to use a correct size washer and tighten it again so that it does not become loose. Posting a pic will help us a lot in helping you.

14th April 2015, 10:49	#1
gopaneel BHPian Join Date: Sep 2012 Location: Bangalore Posts: 60 Thanked: 217 Times	Bike horn distortion at high speed / rpm I own a Honda Unicorn from 2007, the one with spoke wheels. Few years back, I changed the single stock horn to dual Hella Disc horns. The horns are smaller than those on the Pulsar and I really like the way they sound. They are wired with a relay and from what the electrician told me, the horns are isolated from the horn switch and connected directly to the battery. Right from when the horn was changed, the problem I've faced is that the horn sound gets distorted at high speed. My thoughts are, it is probably due to higher current from the electrical system at high speed. But since it is connected directly to the battery, can a higher current flow through? Also, has anyone had an issue of horn distortion at high RPMs? Finally, how do I resolve the issue? Mods, even though my query is regarding a bike horn, I'm putting it in the accessories section because there is a chance that car owners have also faced the same issue. Last edited by GTO : 14th April 2015 at 12:41. Reason: Typo
	() Thanks

14th April 2015, 12:50	#2
bblost Team-BHP Support Join Date: Jul 2007 Location: Hyderabad Posts: 11,284 Thanked: 17,938 Times View My Garage	Re: Bike horn distortion at high speed / rpm My thoughts on this: While the horn is connected to the battery, the battery is still connected to the alternator. So the voltage available to horn is going to be whatever is higher at a given moment. When running high the alternators wires are carrying higher voltage. These same wires are also in contact with the wires that are going to the horns. They will get distorted at high speeds. I don't think its possible to isolate them. The only option is getting horns that are able to work with this voltage range.
	(2) Thanks

14th April 2015, 13:51	#5
rakesh_r Senior - BHPian Join Date: Nov 2009 Location: Pune Posts: 2,088 Thanked: 3,432 Times	Re: Bike horn distortion at high speed / rpm Put the bike on centre stand and with the bike in Neutral rev the engine and check if the problem exists.Also check the horn clips.Tighten them if they are loose.
	(4) Thanks

15th April 2015, 18:03	#6
Technocrat Senior - BHPian Join Date: Feb 2004 Location: GTA Posts: 14,770 Thanked: 2,705 Times	Re: Bike horn distortion at high speed / rpm Hmm so the relay is already in place, how old is the battery? Can you try by temporarily putting a new one in place? Also have you checked to see if the wiring is lose? Also what do you mean by the horns are isolated fomr horn switch? How do you operate them? via a separate switch?
	(1) Thanks

15th April 2015, 18:11	#7
saket77 Distinguished - BHPian Join Date: Dec 2012 Location: India Posts: 4,835 Thanked: 14,725 Times	Re: Bike horn distortion at high speed / rpm Hello Gopaneel, There is an adjustment screw behind the diaphragm of the horn. Use this screw to adjust the tone of the horn and you may hit the right spot. It may be locked by a nut under the screw and may be covered by a tiny rubber housing. You will have to remove the rubber cover to have access to the adjustment screw. Try this procedure and report us back. Regards, Saket
	(1) Thanks

15th April 2015, 19:32	#8
girimajiananth BHPian Join Date: Oct 2012 Location: Bangalore Posts: 675 Thanked: 710 Times	Re: Bike horn distortion at high speed / rpm If you find the horn to be loosely mounted , you may want to use a correct size washer and tighten it again so that it does not become loose. Posting a pic will help us a lot in helping you.
	(1) Thanks