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The Horn Thread

28K views 60 replies 30 participants last post by  Rootch 
#1 · (Edited)
So... the horn. Meep meep and all that mess.

Standard disclaimers apply - I will not be held liable if you cannot execute this on your own without it killing your children or burning your house down. If you have questions, ask, google, so forth...

The horn on the CBR is fairly loud, it's just not much of a "commands attention" sort of frequency. It sounds like a small car or motorcycle... not something that should be avoided when it honks.

Most all of my bikes, I do this swap, someone asked if I'd make a thread, so here's the thread.

Things you'll need:
- Basic mechanics tools (10mm socket, combo wrench, and 5mm allen wrench)
- Various wiring supplies, such as butt splices, 1/4" quick connect female crimps, and a ring crimp.
- Crimpers
- Wire
- An inline fuse holder and a fuse for it.
- A High/Low pair of 132dB Freeway Blaster horns
- cable ties
- relay
- Um, maybe some other stuff.



Strip the fairing off the left side of the bike, take the pillion/cowl off to expose the seat bolts and remove the seat to expose the battery. If you need details on how to do this, I'm not providing them. You *MUST* know how to maintain your bike, and how to pull the fairings off is pretty much the beginning of any and all procedures involving the engine. Look elsewhere for the play-by-play if you need it.

Disconnect the negative battery lead any time you're getting ready to do electrical work.



Pull the fuse box up so you can get a driver onto the positive terminal, and install a ring crimped end on the inline fuse holder and put it on the terminal and screw all that mess back down and replace the bike's fusebox back into its holder.





Attach a long piece of red wire to the other end of the fuse holder. You can use butt splices here, but I chose instead to solder and heatshrink the connection.



Pull enough wire, being careful with the routing of the wire to avoid pinching between things that could chafe the wire or some such (this is really kinda why we have the fuse there, in case something goes wrong) to reach maybe a foot or more past the stock horn location, this should give you enough extra to tie the wire down in a decent routing, etc etc, yadda yadda.



The horns usually come with some hardware kit with them that includes tabs and short wire jumpers so that you can ground one of the two terminals to the bike's frame... Even though this isn't the orientation I ended up using, it looks kind of like this:



Then comes the difficult part... figuring out how to get the horns to fit. One of these horns is larger than the stock horn, and we now have two.

I ended up mounting one more or less in the stock location, and bent brackets around to get the second one next to the engine. I'm not terribly happy with the setup... but it's working so far.

Then, you just wire it up... relays can be confusing, but once you realize they're just a switch that is switched electrically by a switch, it kinda makes sense.

Here's what the terminals on the relay are:



So, we connect the wires that went to the original horn to the 85/86 terminals. Polarity really doesn't matter here, we're energizing a coil. Then, we connect our lead that we ran from our battery and our horns to the 30/51 and 87 terminals. Again, doesn't really matter which way they go here, one is one side of the switch and the other is the other side of the switch. When we apply voltage to 85/86, the switch closes between 30/51 and 87. Really simple stuff, actually.

Then, we take the output from the relay and splice two wires together into one (yeah, i didn't get a pic of that) and run those to the horns.

Use cable ties to tidy it all up and hold it in place, add your fuse to the fuse holder, re-connect the negative brake line, turn the key and watch out for your ears when you hit the horn button.



The difference in sound (doesn't really do anything for showing any difference in loudness):

 
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#2 ·
I have the Fiamm Hornway Blaster Low tone, one was enough for me. Most people seem to hear it.
 
#3 ·
I should have mentioned also - much easier to just do one horn. No relay, or any of the other stuff necessary.

Debatable probably whether or not the two horns really need the relay and long haul back to the battery. I just prefer to keep anything like that off the bike's electrical system if possible, just in case. :shrug:

I prefer the two horns because the modulation of the two notes seems to be more "commanding".

I didn't get it on camera. I honked the truck horn. It isn't as loud, but is almost the same sound.
 
#4 ·
I just swapped out the stock horn for the low tone freeway blaster yesterday and am pleased with the results, best $10 I've spent so far. Considered going with both horns and a relay, but we'll see how the low tone on its own does for a while.

Thanks for the detailed write up!
 
#7 ·
Great "how to" TX_Dj. Wish I had access to it a few years ago when I added dual Fiamms to my old Yamaha 400. Would have saved me a lot of trial & error.

Regardless of posts to the contrary elsewhere on the forum, having had dual aftermarket horns on a bike already I know that they ARE heard and CAN save your bacon. Maybe not in every instance, but that one time a cager hears your modded horns over the stock one is the day you'll be glad you installed them. I'll be adding Fiamms to my CBR soon and this is a great referrence to come back to when I do it.
 
#10 ·
Yes, sendler, thanks for pointing that out, I neglected to mention it in the writeup.

I don't recall who, specifically, but someone on the rebel forum after reading my write-up there years ago, decided instead it'd be better to face them forward. One rain ride and he had muffled water blasters which, shortly thereafter if memory serves, stopped working altogether.

Yesterday on the way home from a friend's birthday party, I had a cager in a parking lot who failed to notice the motorcycle exiting the freeway, and was failing to yield as I was already into the right lane. He was in a nice quiet-interior cadillac, and started pulling in front. I started to evade, but locked on the horn. He snapped to a stop, and his head snapped around and looked for the dump truck that he missed. He was pissed when he realized it was "just a motorcycle" (and that I was so far away).
 
#15 ·
I don't know, that's an interesting theory though.

Some bikes do mount higher up than our stock location, but considering how ear splitting these horns are, I don't think it's going to matter much. :D

Don't know about the police on your side of the rock, but around here, more specifically in Texas, they won't care if it's 1 horn or 1000, mounted to the bike or your arsehole, so long as it honks when you mash the button. :)
 
#17 ·
The stock horns seem to be adequate for places like Asia where traffic congestion is heavy, cars aren't as luxurious, and everyone drives with their windows down.... great idea when producing for a global market and for volume, but sucks over here... where geezers in Caddies can't seem to hear much.

I love riding, but I fear other drivers... thanks for this writeup, I'll probably get myself a new horn!
 
#22 ·
llory, that's about right, It was about $18/ea for the horns, the relay can be had for about $5, few bucks for a fuse holder & fuse, few bucks for the odds/ends.

I didn't write up a price list per se because I already had everything I needed except the horns and fuse holder. Heck, I didn't even end up using the black wire I showed in the photo, and I ended up using a ring terminal not pictured initially and other stuff.


WRX,

I used the straight brackets that came with the horns and the stock bracket and some extra fasteners to get it all in place. I'm not terribly pleased with it, it's definitely a kludge job. I was in a rush to get done so I could clean up and head out to a buddy's birthday party. It's held up just fine, but I've had to re-tighten one of the fasteners already because it had slacked enough to let the rear horn rest on the engine case. I'll post a pic when I come up with a better method.

As for the effectiveness at freeway speeds...

This morning on the tollway, I made a lady SUV driver drop her phone and slam on her brakes when I honked next to her. She was completely oblivious to the fact that she was failing to yield right of way to cars who had it. HONK. comedy. Sadly, the cam only picks up the nose of her car in the periphery for a moment, and then disappears when she slammed the brakes. I was right next to her and one blast at 70 mph caused her to wake up and tend to the task at hand instead of the phone call.

Hi. Please drive while you're supposed to be driving. That'd be nice. The rest can wait.
 
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#26 ·
"Doesn't sound like a wimpy little bike anymore. Kinda glad about that."

Amen, brother!

This morning in traffic, full size truck started encroaching my lane as I passed him, I laid on the horn, he laid on his, mine was louder. :cool:
 
#28 ·
I haven't mentioned in this thread but this the exact setup i've had on my car for about 3 years and I can vouch for the combination of these 2 horns. They will DEFINITELY get attention. The only time I haven't been heard when blowing the horn on my car was on the freeway when an 18-wheeler started to run me off the road, but as you all know 18-wheelers are LOUD at freeway speeds
 
#30 ·
Definitely, but I think they are quieter. Certainly would get the attention of anyone listening. Not too difficult to wire it up as a second horn though.

AaaaOOOOOOgaHHHHH
 
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