Aftermarket Speedo Wiring

[nilsthenomad]

I just bought a new mini speedo off of Dime City Cycles and installed it on my 81' 750K this afternoon. Saw there are a few threads about how to wire these up, and manage to have all the lights working fine, but still having a problem with the blinkers. The speedo has a single wire that leads to the blinker light on the display, but I obviously have two blinker wires. If I hook one of the wires up both the blinkers function fine, but only one lights up the speedo light. If I connect both blinker lights to the one speedo wire, both blinkers flash simultaneously when I turn on the signal. Any recommendations on how to fix this?

[shinyribs]

When you connect them both out causes all your blinkers to flash because it's back feeding at that area and turning your individual ( left and right) blinker circuits in to one continuous loop.

You could wire in a pair of diodes that will prevent back feeding. But diodes are tricky to size correctly and can burn out pretty quick when overloaded. There is a common point of connection at the flasher bulb itself. Whether you are activating the left or right blinkers the flasher bulb always pulses the common + wire that feeds the turn signal switch. If you can determine and tap in to that I think that will be the easiest, cleanest and most dependable option. Even if it does have you running a wire all the way to the flasher bulb.

Hope that made sense.

[surfish95747]

This is the best hand drawn diagram that worked prefect for my 1980 CB750K. Ask any questions if you have them.

[nilsthenomad]

Cool. Thanks for that diagram. I ended up just heading over to radioshack and picking up some 12v diodes for $2 and wired em in. Worked great.

Got nice and clean gauge area now:

[shinyribs]

I've had my eye on that gauge. Let us know what you think of it after you ride for a while.

Glad you got it fixed! :)

[surfish95747]

shinyribs, I love mine so far! I've got around 400 miles using mine now and its great! For my 1980 cb750, its right on every time. LED's are bright and the whole set up is very clean!