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Kuryakin battery gauge review, and why I'm glad I got it!

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AndreRA3:
So, onto round 2 of André's incredibly insightfull, although unsolicited, product reviews:

I installed a Kuryakin battery gauge on my 74/78  Cb750k  today, and was at first a little concerned.

You see, my battery was measuring at 12v exact, while the Kuryakin gauge swore I had only 8v.  Weird.

 At first I thought it was the connections, so I checked everything and all was fine.  I installed the gauge on my handlebars (via the provided double sided tape, but I'll J-B weld it later), and connected the wires to a spare ground and to the gauge lighting wires (both inside the headlight case) by using bullet connectors I bought at Radioshack.  I thought the connections were bad, but as I checked the same wires with my digital multimeter, the measurement agreed with the gauge.

So now I'm weirded out and worried, since I know that those wires are 12v (or whatever the electrical system is putting out).  All this is with the bike running, by the way, and reving it up does absolutely nothing.  Confused, I have the first brilliant idea of the day, which is take out the headlight before I drop it and brake it.  Amazingly, the minute I take out the headlight, the voltage jumps to 13.5 at idle.

ok...  so my headlight is taking up too much juice... but it shouldn't be... it's a 55/60 watt halogen bulb.   I replace it with the dimmer 55/65 watt sealed assembly I had before and BAAM!!!  8v again.  but it jumps to 13.5 when I rev it up.

Huh?

I replace it with the old headlight.  8v again.  14.5 when I rev it up.  12v at idle

WHAT THE %@##???  How??  When??? Why???


In chimes my father, who tells me it's probably a short somewhere (he was freaked out by the rat's nest inside the headlight bucket.  He calls it a rat's nest, I call it my wiring harness).  So we start isolating every connection that could possibly short out (there were a few) with electrical tape and putty.  We turn the bike back on and it says 13.5v at idle.  14.5v revved up. 

Oh Yeah!


Needless to say, we left it at that and reassembled the headlight.  After reassembly all remained well, so hopefully it will stay well.  I still think it's weird that the actual system voltaqe does not match voltage measured at the battery, and for that alone I'm glad I installed the battery gauge.  Maybe its because my battery isnt fully charged, since the bike was shorting out somewhere, but I'm glad I know that now, and thought you guys would like to know.

Anyway, I hope this helps someone...

BTW, I bought the battery gauge on ebay, but I'm sure you can get it at bike stores and such.

André

AndreRA3:
Oh, yeah, I was going to do a short review of the gauge, wasn't I?  ::)

I personally like it.  It's very small, lightweight, easy to install, etc...  I glued mine on the clubman style handlebars I have, and it's barely any wider than the bars themselves.  The leds are very bright, though and easy to read.

I know how well it performs tomorrow when I ride to college, but I see know reason why it wouldn't be as good as tonight in my garage (other than the double sided tape coming off.  If that happens, I'll jb weld the thing down and let you guys know.

That's all I can think of for now....

André

Dennis:
My guess is that there was no short.
I would think that there may have been some corrosion, oxidation or just poor contact in one of those old connectors that you moved around and that when you handled it there was a better electrical contact.
I would suggest that you might want to take each connection apart, inspect and gently clean and reassemble with dielectric grease.
Just my opinion.

oldbiker:
There is no possible doubt, a poor connection is the problem. Obeying the laws of electricity, when there is a resistance with current flowing through it the voltage measured at the two ends of that resistance will be different. In other words since your connection for the guage is taken from the headlight feed wire or is earthed at the headlight earth wire, when you switch on your light the current drawn causes a voltage drop across the high resistance. This shows on your guage.

MRieck:
I agree with the 2 previous posts. That gauge is pretty good looking and the cost reasonable.

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