Topic: Headlight relay

[bollingball]

I have read HondaMans book and a couple of other post her about how to wire this duel relay up.They all break the Black switched power wire on the harness side of the Ign Sw. However on my 750K8 I have the Red wire from the fused Batt. feed this Sw. and then when key is turned on power goes to the black wire. I'm thinking I should break the red wire to feed my relay coil and other side of coil to grd. and let the contacts one on each relay power the headlight hi/low. The K8 has no headlight on/off Sw. Does the sound correct or am I missing something

[bollingball]

TT or HM got any ideas on this? HondaMan I understand your book mostly covers 76 and earlier that is why I'm asking about the 750K8. It may be just the 77-78 wiring with the RED feed wire but it looks like this is the one I need to break.

                                       Thanks Ken

[TwoTired]

The headlight relay idea is to bypass the load going through the key switch contacts, right?

For this goal, you need to use the Black wire as a signal to the relay N.O., and let the relay carry the main power.

If you tap into the red, the headlight will be fused via the main only.  The headlight fuse will be superflous.  But, you haven't mentioned what wire you have chosen to for the Headlight power, and whether you are wanting it powered alone or together with general lighting.

I don't know if you are trying to save the Key switch, or make the headlight brighter, or if you are trying to make the charging system work better.

Cheers,

[Bodi]

the whole idea is to take the headlight current out of the main harness. having the relay coil on the red wire will have your headlight on all the time. The black wire is switched ignition power, so the headlight will come on only when the key is on with the coil powered from it.
I have this relay, with a separate wire to feed power direct from the battery to the relay contact. This comes from an inline fuseholder at the battery with a 10A fuse. The fuse is vital, without it a short to ground from my new wire would probably start a fire and burn the bike down to a smoking frame over a pile of gears in a puddle of melted aluminum.

[bollingball]

Bodi Thanks for the reply I did put the fuse in-line on the red main. Changed them all with newer acc. type like HondaMans setup. On my bike the RED wire is the 15a main and goes straight to the key sw. so I put it back that way. So if I understand you I should still break into the BLACK switched power to feed the coil on the relay. this sounds right to me. Can anyone else confirm TT. HM.? Help!! I want to do it right the first time

                                         Thanks Ken

[swellguy]

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[TwoTired]

There are only four terminals on the relay, usually.

Two of them control the power path.  And, the other two control the internal switch.

You are likely going to use the presence of power on the Black in the harness to activate the relay on.

Unless, you share the relay terminal configuration, and tell me the problem you are attempting to solve, I can't really say much more.

Cheers,

[mrrch]

I just did this on my K7. My two relays are wired directly to the battery with a fuse, the wires that run to the headlight plug are doing the "switching" on the relays.
Do a search for headlight relays and you should be able to find the wiring diagram I used.
I noticed a .2 volt increase at the headlight plug after this mod.
I also plan on adding the relay for the ignition switch(to prevent the cheap Emgo switch from melting the contacts)

[swellguy]

I also plan on adding the relay for the ignition switch(to prevent the cheap Emgo switch from melting the contacts)

Mark (hondaman) sells a really nice little kit for this.