Um... does the Terraplane even HAVE a turn signal??


Heavy Armor

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So I'm wiring this thing into my bike, and looking at the schematic included in the old PDF manual, there's a tail light wire, a brake light, and an "accessory", whatever that is. I had assumed I would just wire the blinker and the brake together on the sidecar, but just realized that can't work, because any time I hit the blinker it would make my bike brake flash, and every time I hit the brake it would supercede my blinker. Now I'm pretty confused as to how I'm supposed to wire this. Did the Terraplane not come equipped to function with a turn signal???
 

Larry Fine

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I faced the came thing when I converted my '82 Nighthawk 750's rear signals to red lenses, and wanted to add brake-light function to them. You'll only need one of what I made two of. I wired a 12v SPDT relay to be controlled by the front marker/position light wire, which turns off when that side's signal is on, for greater flashing contrast.

When the signal is not in use, the rear signal filament gets its power from the brake-light wire, so it lights up steady with the brake. If you turn on the signal, the signal filament instead gets its power from the signal wire, so it blinks. I also converted those rear signals to dual-filament bulbs, like the fronts, but that's not relevant to this topic.
 

Larry Fine

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Note that the relay will normally be energized, so the brighter filament will act as a brake light. If you don't feel the need for the taillight to go off when using the turn signal, just connect the taillight wire to the bike's taillight wire, and only the relay connects to the front marker light wire.
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Heavy Armor

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I'm not quite following... if you're slowing down to make a turn, you have both the brake and the blinker on at the same time. The voltage on the blinker pulses, so there are brief moments when the relay would switch right back to the brake power, no? Operating off the same light, wouldn't it basically stay solid, with maybe just a flicker as it switched from receiving the blinker pulse to the brake signal?
 

Larry Fine

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No, because the relay coil gets its power from the front marker light wire, not the front signal wire. I'm talking about bikes that have dual-filament bulbs (just like tail-light/brake-light bulbs) in the front signals, like every Honda since at least the late 1960s.

The front marker light on each side is on steadily, except when either one side's signal is turned on. So, instead of the front signal flashing bright-dim-bright-dim, it flashes bright-off-bright-off. On Hondas, the right side marker light wire is the light blue wire with a white stripe.

So, because of the relay being powered by the marker light wire, the rear signal light doesn't flash, it responds to whatever happens to the brake light wire. When the turn signal is turned on, the relay drops out, and the rear signal wire is "returned" to the bike's turn signal wire.

The rear turn signal lights from the factory are only single-filament bulbs, so they only flash bright-off-bright-off. On the old Nighthawk, I converted my rear signal sockets and bulbs to dual-filament, so they're taillights, brake lights, and turn signals; what you need on the right.

If you're okay with the rear signal flashing bright-dim-bright-dim, then let the taillight get it's power from the bike taillight wire as it does now. But, if you'd rather it flash bright-off-bright-off like the front, then connect it to the same wire that powers the relay.
 

Heavy Armor

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Ok, I saw that but wanted to make sure. My bike ('03 Triumph Speed master) has zero marker lights, only a headlight and tail light, so I guess this won't work for me.

Do you see any issues arising if I just slap a few automotive diodes on the hot wires to keep the power from bleeding back and forth?

EDIT: aaah never mind, that won't matter either. I think I may just use the recessed light as a tail light and blinker, and add an LED strip across the roll bar to act as a right-side brake light.
 
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guitarzan

Grasshopper
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So I'm wiring this thing into my bike, and looking at the schematic included in the old PDF manual, there's a tail light wire, a brake light, and an "accessory", whatever that is. I had assumed I would just wire the blinker and the brake together on the sidecar, but just realized that can't work, because any time I hit the blinker it would make my bike brake flash, and every time I hit the brake it would supercede my blinker. Now I'm pretty confused as to how I'm supposed to wire this. Did the Terraplane not come equipped to function with a turn signal???
Hello Heavy Armor,
I'm curious to know if you ever did that wiring so that you could have a turn signal on your Terraplane sidecar? I have a 1994 Goldwing SE and I'd like to wire a turn signal on it too but I'm not good at all with schematics and electrical. I'm just curious.
Thank you
 

Heavy Armor

Grasshopper
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Hello Heavy Armor,
I'm curious to know if you ever did that wiring so that you could have a turn signal on your Terraplane sidecar? I have a 1994 Goldwing SE and I'd like to wire a turn signal on it too but I'm not good at all with schematics and electrical. I'm just curious.
Thank you
I wired the marker light as normal, but I wired the sidecar brake light to be the blinker. That left me without a brake light on the sidecar, so I bought a red LED strip and mounted in in the center of the rear, just under the seam, so it behaves much like a car's 3rd brake light.
 

guitarzan

Grasshopper
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I wired the marker light as normal, but I wired the sidecar brake light to be the blinker. That left me without a brake light on the sidecar, so I bought a red LED strip and mounted in in the center of the rear, just under the seam, so it behaves much like a car's 3rd brake light.
Hi,
Thanks for the quick response and the information. Do you have a turn signal?
 

cfmckay

Grasshopper
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When I restored my Terraplane I attached a BMW K bike rear turn signal housing to the wheel fender. It required some modification but works as intended. I have attached a few pictures of my rig.
 

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