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Horn and relay mod question

Started by Bminder, September 18, 2013, 02:11:25 PM

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Bminder

I put a louder Wolo horn on a few weeks ago, just the automotive type, not a compressor type. It works, but not at idle or when the bike is off.
Some of you said I need put put a relay on and wire it direct from the battery, so I went to my Advance Auto store and was looking at relays and inline fuses an such, and the parts guy asks if I need help. I explain what i"m doing and  he says, "That won't solve your problem. You need to upgrade your alternator, because it's still all the same electrical circuit, blah blah blah."  I have limited electrical knowledge so I tried to explain that the horn shared a circuit with the headlight, blinkers, dash light, and the voltage drop at idle is too low to make the horn work, so I was going to bypass it and run it direct off the battery. He kept saying, "That won't solve your problem." and talking about it all being the same electrical system and I need to upgrade the alternator.  He also said it wouldn't be waterproof and would cause problems.
I finally said "OK thanks." and left.

So anyhow, I don't think he's right.  So I should get an inline fuse, run that from the battery to my new relay, run the horn button wire to the relay and a wire from the relay to the horn, and the ground wire from the horn to a ground, as well as ground the relay?  Is that right? What else? Do I need to find the wire from the horn switch going back to the original fuse box and do something with that too?
How do I make this work, or is the parts guy right?
Billy Minder
92 FJ1200 ABS

racerrad8

Did you ask him if he had an "upgrade" alternator for an FJ1200?

Put the relay in. The relay is an electrical switch to allow full electrical current from the battery to the horn with the appropriate size wire instead of using the small Yamaha wiring and switch.

BTW...I have the relays and plug/wiring in stock so you don't have to go t the auto parts store and have someone who knows probably lees than you tell you how to resolve the issue you are having.

Randy - RPM
Randy - RPM

Dads_FJ

Quote from: Bminder on September 18, 2013, 02:11:25 PM
I put a louder Wolo horn on a few weeks ago, just the automotive type, not a compressor type. It works, but not at idle or when the bike is off.
Some of you said I need put put a relay on and wire it direct from the battery, so I went to my Advance Auto store and was looking at relays and inline fuses an such, and the parts guy asks if I need help. I explain what i"m doing and  he says, "That won't solve your problem. You need to upgrade your alternator, because it's still all the same electrical circuit, blah blah blah."  I have limited electrical knowledge so I tried to explain that the horn shared a circuit with the headlight, blinkers, dash light, and the voltage drop at idle is too low to make the horn work, so I was going to bypass it and run it direct off the battery. He kept saying, "That won't solve your problem." and talking about it all being the same electrical system and I need to upgrade the alternator.  He also said it wouldn't be waterproof and would cause problems.
I finally said "OK thanks." and left.

So anyhow, I don't think he's right.  So I should get an inline fuse, run that from the battery to my new relay, run the horn button wire to the relay and a wire from the relay to the horn, and the ground wire from the horn to a ground, as well as ground the relay?  Is that right? What else? Do I need to find the wire from the horn switch going back to the original fuse box and do something with that too?
How do I make this work, or is the parts guy right?

You are right, so is Randy.  Buy the relay and harness from Randy, it will look like this (only smaller):


And to prove the parts guy wrong and make yourself feel better, 'test' the horn by hooking it directly to your bikes battery using a length of wire - bike not even running (alternator not even producing power).  Get the relay and we'll help you after that...
John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20

Capn Ron

And if you need a wiring diagram to help you out...  It's printed right on the side of the relay!

Randy's 5 Pin relay and wiring harness would make your task dead-simple and save you a bunch of crimping.

Relay:
http://www.rpmracingca.com/proddetail.asp?prod=5PinRelay&cat=39

Wiring harness:
http://www.rpmracingca.com/proddetail.asp?prod=RelaySocket&cat=39

Cap'n Ron. . .
Cap'n Ron. . .


There are two types of people in the world...Those who put people into categories...and those who don't.

movenon

yep, do the relay for the horn........... Big sound, big voltage an current draw.  :good2:  The Hella's also require a relay. They sell the relay with the kit.

George
Life isn't about having the best, but about making the best of what you have...

1990 FJ 1200

Bminder

Thanks. That's what I thot. How do I do it and use the stock horn button ?
Billy Minder
92 FJ1200 ABS

racerrad8

Terminal 85 hooks to the original horn wire.

Terminal 86 is grounded.

Terminal 30 is the fused wire from the battery.

Terminal 87 is the horn connection.

Randy - RPM
Randy - RPM

Bminder

This is what I mean about not knowing much about electrical circiuts.
So I just leave the other end of the horn button wire alone? Doesn't that go to the battery too?
Billy Minder
92 FJ1200 ABS

fj11.5

the other horn wire is ground at the switch, stays connected to the horn , as long as its actually grounded unlike mine was :scratch_one-s_head:
unless you ride bikes, I mean really ride bikes, then you just won't get it

84 Fj1100  effie , with mods
( 88 ) Fj 1200  fairly standard , + blue spots
84 Fj1100 absolutely stock standard, now more stock , fitted with Fj12 twin system , no rusted headers for this felicity jayne

racerrad8

Come on now...electrical is easier than A/C work...

The second horn wire is a ground, so you can hook that to terminal 86.

It really doesn't matter which of the two wires hook to 85 or 86.

Randy - RPM
Randy - RPM

Bminder

Quote from: racerrad8 on September 18, 2013, 05:17:20 PM
Come on now...electrical is easier than A/C work...

The second horn wire is a ground, so you can hook that to terminal 86.

It really doesn't matter which of the two wires hook to 85 or 86.

Randy - RPM

It is? Ok then.
Thanks, I'll put an order in!
Billy Minder
92 FJ1200 ABS

skymasteres

Quote from: racerrad8 on September 18, 2013, 05:17:20 PM
Come on now...electrical is easier than A/C work...

The second horn wire is a ground, so you can hook that to terminal 86.

It really doesn't matter which of the two wires hook to 85 or 86.

Randy - RPM

There must me something strange going on with my FJ because I tried this and one of the horn wires is hot to the positive battery terminal, and the other grounds when I hit the horn button. Aaaaaaannnnd I just figured out why it isn't working....

You have to use BOTH horn wires. One on 86 the other on 85. I had a separate ground on 86 (straight back to the panel) so there was no power going to the horn switch when the horn ground was plugged into the relay. Since the other horn wire is always hot it would constantly run the horn regardless of switch position. If you use them both you fix the issue and save a ground wire to the relay for the coil.

skymasteres

You can actually use the original horn bracket to mount the Wolo.
Just trim the nut off and pound it flat retaining the right angle and gusset.




If you are running a stock headlight plug you'll be fine clearance wise. If you have a ceramic plug it'll be darn close.
(I removed the plastic Wolo plate to get an extra 3/16" of clearence)




Talk about LOUD!