Adding a relay to the headlight.

[camos]

I've been thinking about adding a relay to power the headlight hi/lo directly from the battery, essentially bypassing the connection through the CMU. It could be done using one relay with normally closed going to the lo beam with the switched circuit going to the hi beam operated by the dimmer switch. Or alternatively using one relay for each of the hi and lo beams.

 

I pulled this quote from another thread.

I had a problem with the head lights also on bike before its rebirthing this winter.... I added a relay connected to the dimmer switch that directly switched hi-lo beam.

Gary

Gary what relay option did you use? The first one would seem the simplest but may not allow the lo beam to be shut off by the start circuit.

[wes0778]

Gary may chime in with a G1 specific option, but on my G2 I picked up a single pole single throw 30Amp relay from Autozone. I cut into the "feed wire" to the dimmer switch. I hooked the cut end going to the dimmer switch to terminal 87 on the relay and the other cut end to terminal 85 on the relay. Terminal 30 on the relay is hooked to a fused wire directly to the positive battery post and then hook 86 to a suitable ground.

 

Also as a safety measure in case the relay fails, I wired a manual off/on switch across terminals 30 and 87. This switch turns on the head, regardless of the position of the ignition switch.

[camos]

I cut into the "feed wire" to the dimmer switch. I hooked the cut end going to the dimmer switch to terminal 87 on the relay and the other cut end to terminal 85 on the relay. Terminal 30 on the relay is hooked to a fused wire directly to the positive battery post and then hook 86 to a suitable ground.

 

Also as a safety measure in case the relay fails, I wired a manual off/on switch across terminals 30 and 87. This switch turns on the head, regardless of the position of the ignition switch.

So the dimmer switch receives power from the relay rather than the headlight? I think I may be confused.

 

Seems to me using one relay would require using a 5 terminal relay with switched power from the dimmer to 86/85 to ground. Connecting from the battery to 30 with 87 connecting to hi beam and 87A connecting to lo beam. This provides a direct connection from battery to lights through the relay eliminating the undersized Yamaha wiring and switches. What it doesn't do is turn the headlight off when starting.

[dingy]

You could accomplish the High/Low beam function with a single DPDT relay. This relay will have 87 & 87A contacts.

 

This would eliminate the CMU and the reserve lighting unit from circuitry.

 

Circuit is shown in attached PDF.

 

This circuit will not however address CMU warnings, or need to feed power to CMU.

 

I just sketched it up to show head light circuit.

 

Gary

[camos]

Thanks for the schematic Gary. Is the headlight fuse and the start switch already in the circuit or does some rewiring have to be done to get it that way? Also would not running the main light feed through the start switch somewhat choke the feed to the relay?

 

What I have been leaning towards doing is to add two relays, one each for hi and lo beams. Tapping in to the hi/lo beam wires near the headlight to power the relays should, I think/hope, address the warnings while bypassing the skinny stock wiring through the CMU for the headlight. If the relays do not have enough resistance to cancel the warning some resistors could be added to help out. This method should still allow the lights to be turned off by the stock start switch while supplying power for hi/lo directly from the battery.

 

I have yet to investigate the reserve lighting and do not even know what that is, other than the obvious, or how it works.

[dingy]

Thanks for the schematic Gary. Is the headlight fuse and the start switch already in the circuit or does some rewiring have to be done to get it that way? Also would not running the main light feed through the start switch somewhat choke the feed to the relay?

 

What I have been leaning towards doing is to add two relays, one each for hi and lo beams. Tapping in to the hi/lo beam wires near the headlight to power the relays should, I think/hope, address the warnings while bypassing the skinny stock wiring through the CMU for the headlight. If the relays do not have enough resistance to cancel the warning some resistors could be added to help out. This method should still allow the lights to be turned off by the stock start switch while supplying power for hi/lo directly from the battery.

 

I have yet to investigate the reserve lighting and do not even know what that is, other than the obvious, or how it works.

 

 

Look at my third post in this thread for description of reserve light operation.

 

http://www.venturerider.org/forum/showthread.php?t=47671

 

Headlight fuse and start switch are already in circuit I showed above.

 

Relays will probably already be too high of resistance to activate warnings. What you need is current flow to cancel warning. This is lower resistance. The relay draws about 1/4 amp, 55 watt bulb would be around 5 amps.

 

Gary