To coil mod or not?

Cuff wrote: Thank you for the info. I do have my relay, ignitor, main ground and regulator hooked up to it. Would this help?

It depends on which side of the switch those items are hooked up on.

This first way is bad.



This second way is fine, as long as reg/rec ground and battery ground get removed from all of the other grounds by the cutoff as shown.

I have it as you do in #2 but with the addition of the igniter to the same ground. No points. I also have the relay going to frame ground. Should I be grounding the igniter to the frame thus keeping it seperate from the Reg/Rec?

Thanks again for the peace of mind and any further help.

Sorry for the edit.

loudhvx wrote: On one of my bikes, I use relays for an integrated brake/turn signal controller. The first place I had the relays mounted suffered from vibration. They vibrated open/closed rapidly at high RPMs.

I wonder if that is whaat is making my bike cut out and sputter at anything above half throttle? I have the relay mounted by the battery.

Never rely on the frame as a ground if you can run an actual ground wire instead.

The frame should be grounded, though, as that is how the horn is grounded (through the bars etc.), and other things may use the frame ground too.

The igniter and relay should all ground to a main ground wire which connects toone side of the cutoff switch. The battery and reg/rec should be on the other side of the cutoff.

(Incidently, in case anyone does it, if a cutoff is installed on the positive terminal of the battery, the reg/rec output needs to go to the battery side of the cutoff.)





The only difference in the two drawings is where the reg/rec ground attaches.


The igniter, itself, doesn't use much power, so it can be wired to the kill switch as normal. This is safer since killing the ignition or kill switch will kill the motor regardless of the relay.

As a matter of fact, an argument could be made that you don't need the relay at all. You could just hardwire the coils directly to the battery positive. The igniter would act as the relay via the kill switch. But I don't recommend it, since then you are relying on the igniter to not fail. (Just as a points bike with coil mod is relying on a relay to not fail.)

Matteson wrote:

loudhvx wrote: On one of my bikes, I use relays for an integrated brake/turn signal controller. The first place I had the relays mounted suffered from vibration. They vibrated open/closed rapidly at high RPMs.

I wonder if that is whaat is making my bike cut out and sputter at anything above half throttle? I have the relay mounted by the battery.

Possible. Very easy to check, just unmount it, and suspend it with tape or wrap it in a plastic bag etc., temporarily, to test it. Just make sure vibration can't get to it.

loudhvx wrote: On one of my bikes, I use relays for an integrated brake/turn signal controller. The first place I had the relays mounted suffered from vibration. They vibrated open/closed rapidly at high RPMs.

The one main relay I have on mine: I wrapped it in foam tape and then electrical tape. I mounted it to the frame by wrapping tie-wraps around the wire leads going into the relays, the relay body just rests against the frame. Anything electronic has to be cushioned from the frame or it will be destroyed by vibration.

Thanks again loudhvx for the peace of mind. Now to just figure out why I'm getting a dead plug every now and then on cylider #1. another time and place though.

The coil mod has gave me only excellent results and better spark. Just remember to maintain the kill switch wired to shut off/on the relay.