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Discussion Starter · #1 ·
Where is the test for the 7v reg for the temp gauge? Or how is it done.Its not in my tech manuale. I know the gauge is good since my other engin did the same thing showed temp for a little bit then quits. Some times it tryes to work alittle. cx500c 81
 

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What bike?

its up behind the gauges on a ZAB and strapped to the (Tacho?) on a custom



Whichever it is , its got three wires.

Black - Supply at ignition on

Green - Ground

Yellow - 7V output to gauge



Ensure supply/ground is good then trace the 7V output

through the gauge to the sender



No or low output = bad regulator = get another one



Often just checking and cleaning connectors gets em working



If you can trace the 7V to the sender on the green/blue wire

short the sender wire to ground for say 10 seconds in which time the needle should

rise to hot.

Disconnect before the needle reaches the red area of the gauge.

no point in burning it out.



never known a sender to fail but I guess its possible.
 

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Discussion Starter · #3 ·
Thanks. This is the second engin and the older one did the same thing. So I an sure that it may be connetions at the wire harness or the regulator, which I have seen befor when I rebuild the head light. I thought that there was a test that was talked about that could be done with the regulator off the bike. I would like to test the older one from my parts bike. Perhaps I will have to put it on and see. cx500c 81
 

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Thanks. This is the second engin and the older one did the same thing. So I an sure that it may be connetions at the wire harness or the regulator, which I have seen befor when I rebuild the head light. I thought that there was a test that was talked about that could be done with the regulator off the bike. I would like to test the older one from my parts bike. Perhaps I will have to put it on and see. cx500c 81
Well, if you supply it with ground on the green wire and 12 volts on the black wire, it should produce 7 volts output compared to the ground on the yellow wire.
 

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That's one of the first things I'm going to do when I get back over to CXOkies as we're putting everything back together - remove, clean and re-establish all the ground points then cover them all with a little clear nail polish or something.



Oh, and if your 7V regulator turns out to be bad it's easy to build a new one with common parts from Radio Shack, or to build a better one if you order a true 7V regulator IC for about $1 + postage.
 

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Mouser.com will sell you a 7807 if you need one

Mouser Part No: 755-BA17807T



Sadly, in the UK the minimum order makes it too expensive

but there are easy cheap alternatives which keep DIY versions sub £1
 

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Discussion Starter · #7 ·
Thanks guys. I did a resistance test on the 81 regulator and the 80 one. I have found that one check was higher on rersistance then 80 reg. In other words one test showed that by swaping the negative and positive with the ohm meter I then found one difference. I install the 80 regulater and it works as it should. I have two hits on the internet that have the regulator in stock, used. Building one has been approched on this net befor. I just do not remember everything.

cx500c. It's my ugly and I will ride if I want to, ride if I want to. You would ride to if you had one to. ki4
 

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Hey I like those De swad switching regulators

very nifty little things !

I have a few projects on the go that I could use them for

Thanks for the heads up Jason.

Way to good to waste on a temp gauge though IMO

a 78XX will do for that
 

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Discussion Starter · #12 ·
I've had one of,"Reg's" cheap 7v regulators in my bike for several months.Still working great,



http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=8&t=257



Thanks Shep. Thats what I was looking for. I have removed the old epoxy on the 81 regulator to see the parts. Meanwhile the regulator from my 80 parts bike proved to be in good working condition. The prior owner my have had it replaced since it looked so new.

The testing of the regulator would not be complete if there is no load to work the regulator such as the temperature sencor at the thermostat which would very the resistance to the regulator.

The old regulator used five componets, regulator,diodes,filter capacitor. Good thing the markings are still readable.

Just may thoughts.

.
 

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Discussion Starter · #13 ·
I've had one of,"Reg's" cheap 7v regulators in my bike for several months.Still working great,



http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=8&t=257



Thanks Shep. Thats what I was looking for. I have removed the old epoxy on the 81 regulator to see the parts. Meanwhile the regulator from my 80 parts bike proved to be in good working condition. The prior owner my have had it replaced since it looked so new.

The testing of the regulator would not be complete if there is no load to work the regulator such as the temperature sencor at the thermostat which would very the resistance to the regulator.

The old regulator used five componets, regulator,diodes,filter capacitor. Good thing the markings are still readable.

Just may thoughts.

.
 

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The regulators on the UK CXs are a PITA to get to as they are at the back of the clocks and even with the clocks off the bike it is still a PITA to get the Regulator out so I gave up and just left it in and bypassed it with the Reg's REGulator(Pronounced Redgeulator<grin>)
 
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