Minibike wire accessories to ground or negative terminal?

[Kurtatron]

I’m trying to wire some lights on minibike. Right now it only has a single halogen headlight wired directly to charging coils. I want to add more lights and a horn.

How does wiring a battery work? I’ve already got fuses lined up, but I’m not an electrical person. Do the negative side of accessories go to a ground on the bike?

Currently the bike’s ground is the engine block itself. Should I wire all accessories to that? And then do I wire the battery’s negative post to the ground? The frame does not have any grounds on it now.

I’ve never been super clear on the difference between ground and a battery’s negative post.

Thanks.

 

[mk378]

Does it have a battery now? On a battery-less small motorcycle or scooter, the lighting coil produces AC which is used directly by the lights. It can't be readily connected to a battery.

 

[Kurtatron]

Does it have a battery now? On a battery-less small motorcycle or scooter, the lighting coil produces AC which is used directly by the lights. It can't be readily connected to a battery.

I know all this. I know about regulators/rectifiers.

The only question I have is about ground vs negative.

 

[mk378]

There is always a heavy ground wire from the battery minus to the engine and the frame. Electrically these points are at the same potential so you can connect to either. Lots of connections to battery minus can be a maintenance issue due to corrosion and the need for battery replacement.

 

[Hall]

I’ve never been super clear on the difference between ground and a battery’s negative post.

The actual "ground" is (are) the metal points on the frame, engine, etc, not the battery.

 

[Kurtatron]

The actual "ground" is (are) the metal points on the frame, engine, etc, not the battery.

So what does that mean if all the circuits+battery do not have any connection to ground (frame/engine)?

 

[repairman54]

As long as the engine is not rubber mounted then engine and frame are connected aka grounded. If engine is rubber mounted then a jumper or bonding strap can be used from engine to frame. Just like what's used in automotive applications.

 

[Kurtatron]

There is always a heavy ground wire from the battery minus to the engine and the frame. Electrically these points are at the same potential so you can connect to either. Lots of connections to battery minus can be a maintenance issue due to corrosion and the need for battery replacement.

AI tells me not to wire to the battery negative, but it doesn’t tell me why. Forum post explanations are equally unhelpful. So if I wired all accessories (except for kill switch) directly to negative side, there won’t any issues, as long as the battery negative also goes to ground?

 

[Kurtatron]

As long as the engine is not rubber mounted then engine and frame are connected aka grounded. If engine is rubber mounted then a jumper or bonding strap can be used from engine to frame. Just like what's used in automotive applications.

Engine is rubber mounted, but I’m still confused. Why does anything beyond a kill switch need to be grounded? Why can’t my lights just go to the negative post without worrying about connecting the battery negative post to ground?

 

[repairman54]

Its ok to go to the negative post. I've put LED lights on snowblowers, with no battery using a rectifier and frame grounds and riding mowers with batteries using the frame for grounding the LED lights with zero issues. As long as battery is connected to the frame it's still a common pole making for less wiring.

 

[wtd]

You can ground your lights at the battery with no issues. Any ground on the vehicle originates from the negative side of the battery anyway. There is always going to be wiring going from the negative side of the battery to either the frame of the vehicle, the body of the vehicle, or the engine of the vehicle or maybe all three. A vehicle will have multiple grounding points which ultimately always lead back to the negative side of the battery.
An electrical circuit is basically a big circle and every load has to have a power and a ground to operate.

 

[Hall]

So what does that mean if all the circuits+battery do not have any connection to ground (frame/engine)?

Where are these other electrical bits grounded ?

 

[Kurtatron]

Where are these other electrical bits grounded ?

I’m asking what are the consequences if nothing is grounded to the frame/engine.

What if my taillights, headlights, and turn signals route straight to the battery negative and positive? Ignore the other stuff like fuses.