Topic: Aftermarket speedometer wiring question

[MattyK]

I bought a new speedo from DCC (http://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-electronic-parts-mini-black-face-led-speedo-speedometer-25-7032b.html) with the indicator lights built in. Here comes more wiring...anyway the gauge came with a sheet of paper that tells you what each color wire represents (ten wires). according to the paper each light has a + and -, however according to the wiring diagram my 74 cb550's indicator lights dont all have a ground wires, the only one with a green wire is the high beam. I tried connecting the wires from the bike (two for each light) to the + wire on the gauge. I did this for all four and then grounded the - gauge wires, blew 15 amp fuse everytime. I then tried connecting all - gauge wires to the green wire in the high beam light. Same thing. So what should do next? I have two live wires for each light and only one for each gauge light...

[wowbagger]

High beam - red to blue, black to ground

Turn - black to a spare ground, red needs to be split and a 1N4001 diode soldered to each. Then, plug one red into orange and one into light blue.

Oil - black to blue/red, red to black

Neutral - black to green/red, red to black

If your oil and neutral lights don't light up you will have to feed them from separate black power feeds.

Note: when I say red I mean + and black is - on the new gauge except for the black powe feed on the original harness for the oil and neutral.

[MattyK]

Thanks! I'll give it a shot, why the diodes? Does that have something to do with keeping the power from each blinker seperate?

[motosan]

I was just about to order the same gauge!  That one looks great.

Out of curiosity....the diagram says Orange goes to - and Light blue to + (I'm just guessing since all the + connections wowbagger said are on the right side of two). 

I mean, is that really how the turn light is wired?  Or did they miss something in the diagram? 

just to clarify...i am NOT challenging you wowbagger.  I'm just clueless when it comes to electrics and trying to understand this diagram business. 

[MattyK]

Clarification on the blinker light would be appreciated, now its the only one im having trouble with!

[MattyK]

Nevermind! Motosan, chenck out this thread, it explains it well. Page two and about a quarter page down where he explains the diodes.

http://forums.sohc4.net/index.php?topic=106175.msg1210267#msg1210267

[wowbagger]

Yeah, the turn light is fed by a double positive circuit. So, depending which blinker is on, the current flows either one way or the other through the bulb. An LED can only work with current flowing one way. The additional diodes allow the current to flow in the right direction, and only the right direction.

[motosan]

Yeah, the turn light is fed by a double positive circuit. So, depending which blinker is on, the current flows either one way or the other through the bulb. An LED can only work with current flowing one way. The additional diodes allow the current to flow in the right direction, and only the right direction.

Thanks for the education wowbagger, you are awesome!

Nevermind! Motosan, chenck out this thread, it explains it well. Page two and about a quarter page down where he explains the diodes.

http://forums.sohc4.net/index.php?topic=106175.msg1210267#msg1210267

nice!!  the build looks interesting.  I'll surely read this through.  Thanks Mattyk!!

[CustomUnderdog]

Hey did you get any feedback on how to wire your mini speedo. I just purchased the same model and have the same problem. Need some help, honda CB750K8

[alacrity]

They usually provide a schematic with the part... In the box.  You didn't get one?


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[alacrity]

Or:  http://www.jpcycles.com/instructions/pdf/5600262.pdf


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