Turn Signal question

Old Guy Too Many Bikes

Well-Known Member
My 12 volt YX140 powered CT70 has been burning out tailight bulbs. Not very often, maybe one every couple of hundred miles. They're aftermarket lights as well that use small indicator light type bulbs. So I replaced both rear bulbs with LED bulbs. Now when I use the turn signals, both rear lights come on, the one I want is a little brighter than the other. On my other bike, I use LED bulbs front and rear for turn signals and have no issues (though I had to switch to an electronic flasher). I still use regular bulbs in front and the old school flasher on the CT. I think it has something to do with only one indicator light for both right and left. Can someone enlighten me. Since the YX has no provision for a neutral light, I thought maybe I could use the neutral light for a turn indicator and have individual indicators for left and right. (I'd have to replace the green lens with an amber one). Or maybe I should try an electronic flasher?
 

Deoodles

Well-Known Member
Place 2 diodes one for left and one for right between the orange and light blue before they plug into the indicator bulb. This prevents power from crossing over from one side to the other when used.
 

Old Guy Too Many Bikes

Well-Known Member
I thought I was a smart guy, but I can't get my head wrapped around this. On a vehicle with two indicators (L & R), it's simple, each has its own independent circuit once it gets past the flasher. The way I understood it with a bike with only one indicator, rather than the indicator bulb being grounded to green (or frame), they're wired to each other so that the right uses the left bulb filament as a ground and visa versa. (Right turn signal on, + flow to indicator bulb, - flow through filament of left turn signal and to ground completes circuit, since left is off). I understand that a diode is a one way valve for electrons, so wouldn't adding diodes prevent the negative side of the indicator light from reaching ground? Wiring two indicators is looking more attractive.
 

Deoodles

Well-Known Member
Solder 2 diode outlets together. Connect to 1 side of the indicator. The other side of the indicator is your new ground. Feed the diodes with the orange and light blue and done. I make a diode jig it is a “Y” and plug it in so no wire cutting.
 
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WarnerSteel

Active Member
Does your speedo have a turn signal bulb? If so, take the bulb out of the speedo indicator light. The LEDs are back feeding thru the speedo bulb.
 
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