Electrical question, wires.

[iMark]

If I want to connect a device that is 12v @20-30 amp
(air compressor horn )

5 amp wire
Rated for Side Tail and interior lights, Car Stereos and Aerials, & Car Alarms

8amp wire
Rated for Brake and Hazard Lights, Rear Fog Lights & Electric Windows

17 amp
Rated for High Output Headlights, Halogen Fog Lamps, Rear Screen Heaters & Wiper Motors

Halfords site also says 27 amp is rated for Charging Cable for battery feed and ammeter circuits which will be over kill.


Electrics isn't my thing but I was thinking the standard wiring would burn out on that kind of horn compared to the standard horns.
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K8 GSXR 1000
"G" : you got him to have a look at a forum which seems to have established a picture of an erect penis in a cat's mouth as it's mascot and thought he might consider it ok?

[Aff]

Just use some 12AWG (about 3.3mm²) wire straight from the battery, with fuse and relay where appropriate.
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Current Bikes:Honda 929RR Fireblade, Honda CD200 Benly (Project), Stomp Z2 140
Electric Bike Project

[stinkwheel]

20-30A is a LOT of current for a motorcycle to be producing on top of the normal load.

Pretty much what the entire rest of the bike with all the lights and acessories turned on will be drawing.

Did you mean 20-30 WATTS rather than AMPS.

A 30W device would be drawing 2.5A. About the same as two brake light bulbs.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[iMark]

Not a clue Stinkwheel, I'm not very savy when it comes to electrics haha... the ad says 12v@20-30a

https://i.imgur.com/9T5hJJr.png

They recommend using a 20-30 amp fuse but is that before or after the relay? haha
____________________
K8 GSXR 1000
"G" : you got him to have a look at a forum which seems to have established a picture of an erect penis in a cat's mouth as it's mascot and thought he might consider it ok?

[Aff]

[davebike]

Running current is 10/12amps but start up is best part of 30amps

You will meed think 25/30 amp wire straight from the battery with a 30amp fuse close to the battery with a 30 amp relay the coil run by the original horn wires
The earth connection also need to be high 30amp rated wire
All connectors need to be good

I run a similar horn myself
____________________
Dave
NC750Xdct + others at work !
davebike1@gmail.com

[iMark]

Might just stick with the normal snail horns, just need to piggy back wires from one to the other if I get dual... much easier
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K8 GSXR 1000
"G" : you got him to have a look at a forum which seems to have established a picture of an erect penis in a cat's mouth as it's mascot and thought he might consider it ok?

[Tamsin]

360W horn, wowzers!

[Stephenniall]

I run a horn very similar (If not the same) to the air horns above.

I have a 30A Relay wired from the battery, to the OEM Horn circuit.

You will break something just wiring it directly to the normal horn circuit.

I have had the horns on for over 2 months now on this bike, and over 6 months on the scooter I had previously, with no 'ill effects'

I wired them in using the wiring diagram I found online below .

https://www.modernvespa.com/pix/uploads/stebel_on_gtv_medium_352_821.jpg

Yes It's for a Vespa, but is standard to most Japanese motorcycles. The only real time that wiring diagram will not work is with AC systems, or Positive Earth (If they made any bikes with positive earths!)