Quick Grounding Question

[J_C]

Hi folks,

I'm installing my new horns using their supplied directions here: http://www.bikerhiway.com/installinf...um_install.pdf

As you can see, I'm rerouting one pair of the old horn wires to the relay at 85 and 86. It says to cut them and use new wire, I don't know why, but I'm going to leave them as they are and use the existing connectors to link to the relay.

Anyway, my question is concerning chassis ground. Chassis ground is any point on the motorcycle frame right? Earn horn has two spades. I'm just planning on running a very short wire from the negative spade of each horn right back to the point on the frame where I'm screwing in the mounting bracket. Is this acceptable as a "chassis ground" point?

Thanks so much!

[Guest]

I would put them under the turn signal ground at the back of the stalk.

[J_C]

I could do that, but it would be a lot tougher. I'm actually mounting the horns on those little square brackets on the front of the frame. These things are big!

[andrewclaycomb]

Our bikes are notorious for having poorly grounded frames. You might run an auxiliary ground wire from a known good ground on your bike to the horn grounds.

[earlfor]

If your stock horns are wired normally, the negative side is the switched sided (going through the horn button) and the positive side is always hot when the ignition is on. Its opposite to everything else on the bike.

Earl

Hi folks,

I'm installing my new horns using their supplied directions here: http://www.bikerhiway.com/installinf...um_install.pdf

As you can see, I'm rerouting one pair of the old horn wires to the relay at 85 and 86. It says to cut them and use new wire, I don't know why, but I'm going to leave them as they are and use the existing connectors to link to the relay.

Anyway, my question is concerning chassis ground. Chassis ground is any point on the motorcycle frame right? Earn horn has two spades. I'm just planning on running a very short wire from the negative spade of each horn right back to the point on the frame where I'm screwing in the mounting bracket. Is this acceptable as a "chassis ground" point?

Thanks so much!

[posplayr]

The answer to your question is Yes

I think so or at least a definite maybe?

Anyway more explaination required. Any part of the frame (except forks, triple clamp or swing arm) should have a pretty good low impedance path back to the negative side of the battery. There are at least two paths to through the frame to the negative side of the battery.

The primary way should be through any bare metal on the frame to a negative side battery ground strap. On my GS750 that would go from negative terminal to a bolt on the front of the battery box but below the rubber grommet (I'm pretty sure). If it is at the bottom the center will bottom out and the ring lug will get squeezed between that and the frame.

The other way is the engine which has multiple mounting bolts which will probably act as additional grounds as the engine case also has the strapping starter return to the negative battery post.

So unless you have a brand new POR-15 painted motor and you lost your battery box ground strap (or just add one) you should be able to attach anywhere on the farme for ground return.

As a test remove the negative terminal from the battery and then buzz (technical term) from your planned ground points to the negative side of the battery cable. This should be less than >1 ohm.

If you have a neg battery ground wire going into the harness and nothing going to the frame add the frame ground strap.

From looking at the supplied schematic, you are doing everything right.

Posplayr

[J_C]

very cool, thank you all. posplayer, I will certainly try that. Which of the settings on my multimeter test that? I have a section that has V-, another with V~, and one with A-. I also have one that looks like a horseshoe, and some other junk.

[posplayr]

Volt Ohm Meter (VOM) Primer

very cool, thank you all. posplayer, I will certainly try that. Which of the settings on my multimeter test that? I have a section that has V-, another with V~, and one with A-. I also have one that looks like a horseshoe, and some other junk.

V - would be DC volts. If it doesn't auto range select 20 volt range (for your 12 volts system). This is for checking Direct Current (DC) voltages. Use this to measure nearly all voltages on the bike. You can put the two leads across anything on the bike and it will not short(i.e. safe even when the bike is running).

V~ would be AC volts. This is for alternating current (AC) voltages With out looking at it, there is RMS and Peak. You should look at your manual to see which your meter measures but i would guess RMS. Use this for measuring stator voltages which are AC. You can't hurt anything measuring with the leads as this should also have high impedance like DC volts. It just wont read DC well the way DC wont read AC well.


A-. Is a amp meter to measure current. You would open a circuit (tail light or blinker) insert the meter in series and it will tell you how much is flowing. You might have to change the probes along with the meter settings. Mine has both a 10A and 300mamp range(plugs). This is because this can be more dangerous and there are different fuses and circuits depending upon range. Don't put it to amps and try and measure battery voltage (can we say dead short). Always make sure there is something with resistance in the circuit. You amp meter will likely have a 10 amp limit and this is not enough to measure something like starter current

horseshoe is "Omega" which is the Ohms symbol . This is how you measure resistance. Generally it is best to make sure the whole bike is un-powered when using this (disconnect the battery). The ohm meter sends a little current out using and internal battery and depending upon how much current comes back it knows how much resistance. Less current more resistance, more current then less resistance. There is usually a 9V battery in the meter that is used to supply the voltage. If you short this across the bike battery it won't work well either and might damage the device. Best practice is to disconnect the bike battery then you cant harm anything with the VOM set to ohms.

Better meters are better protected.

Posplayr

[J_C]

Awesome thanks for the tutorial! I just used the resistance feature on a few items. Set to 200, My keyring gave me a 1.6 and a pen clasp said 3.0 So on the bike, between the ground and the negative battery terminal should be less than 1? Thanks again!

[posplayr]

Check the horns

The GS1150 horns i bought seemed to be about 3 ohms as I recall. If that is the case you want much less than 1.0 ohms drop for just a ground connection. On the other hand for the charging system it is tough to always get it below 0.1 ohms.

Posplayr