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I'm bothered that my 1984 GL650 has no ammeter, and I'd like to fit one myself. What is the spec for the ideal ammeter? And where should the two wires be attached?
 

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That's interesting. Does the indicator normally stay "green" when you're on a run? Does it go amber immediately after you've started from cold, then go green when you've run for a few miles?
 

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AFAIK an ammeter is used to tell if the bike is charging its battery or draining it and how much. One of the Silver Wings (faired) that I owned earlier came with one. I thought it was a nice and useful accessory. It was sitting in a separate 3-instrument console inside the fairing, just above the headlight adjuster knob. Now if memory serves..



I can´t tell for sure, (I´m no electrics guy) but believe that you´ll have to use a couple of rather fat cables to the instrument, coming from somewhere near the main fuse and the starter solenoid. As said - my memory isn´t very precise, but I fitted an ammeter to a SAAB 2-stroke many decades ago and believe it was something like that...



Maybe an ammeter can be used differently. I don´t know.



A diode will only tell about voltage. Quite useful and mostly all we need to know. More than around 13 volts and it´s not draining the battery. And it´s easlily installed without any fat cables (fusing issues) along half of the bike´s length.



Sture
 

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Sture is correct an ammeter would have to have fat cables. The common automotive type would also put some extra drain on the system.

A voltage indicator gives the bonus of telling you if the regulator has failed and the system voltage is too high which you wouldn't know from reading an ammeter.





That is a pretty neat unit BlindStitch suggested. The output table in the ad shows a good bit of information for one little light.
 

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there is a massive difference between an amp meter and a voltage monitor.

look at the cable that goes from the solenoid to your starting motor.....it carries amps




now look at the wires to any light bulb,it carries volts and very little amps.
 

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Ok so the voltage light that i linked works like this.



On my bike when I turn the key it usually blinks yellow or shows red depending on the draw. As soon as I start the bike it shows amber. Usually It takes about a minute and the bike glows green.



I have it hooked up to the aux power on my bike and then it's got a ground running to the ground wires.
 

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I have an ammeter on the CX-Periment.

You wire it across the terminals of the main fuse on the starter relay, then intall a replacement (blade-type) fuse somewhere in the heavy-duty cable to the gauge.

The cable needs to have sufficient load-carrying properties to handle ALL of the bikes electrical system, ie: heavy duty!







An ammeter is not a particularly useful instrument to have on a bike a voltmeter being more suitable, but i had one lying around, so i used it..

I like gadjets, me.





FarklesRus.
 

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Beg to differ. Most amp meters come with a shunt resistor that mounts right at the battery then you run two small wires carrying the signal voltage to the meter itself.
 

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marshallf3 is correct about some ameters coming with an "external" shunt resistor (ALL ameters are Voltameters with a shunt resistor, as operating current does NOT go through the meters coil). The smart way to do it is just as Eurovee indicated by placing the proper "shunt" resistor in line with the main power cable, that way allowing the wires to be small (as they DONT carry the current, they carry the differential voltage across the shut that is generated by the current).



Shunt value will be very small (more than likely less than 10 ohms, and of suffecient wattage for heat disipation) and based on the voltage swing of the meter being used (full scale delection)relitive to the normal full load current. Also, to be any real use it should be a cetered meter (displaying both positive and negative for charge/drain).



I would not recommend using a "true" ameter (built in shunt) and running heavey wires, as if you have a problem with it you will loose all power to the bike.
 

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Beg to differ. Most amp meters come with a shunt resistor that mounts right at the battery then you run two small wires carrying the signal voltage to the meter itself.


Not the one i used as in the pic.

It`s a `classic` type ammeter which is basically wired in series with the battery.

Never seen one with an external shunt, not that i`ve seen that many ammeters anyway...



Also, to be any real use it should be a cetered meter (displaying both positive and negative for charge/drain).



I would not recommend using a "true" ameter (built in shunt) and running heavey wires, as if you have a problem with it you will loose all power to the bike.


The one i used shows demand from the battery : a -ve display , and flow into the battery showing charging is taking place: a +ve display.

Not much point if it didn`t show both!

They`re a useful indication of how the charging system works and behaves, and can be used to check if loads are working correctly, but they`re a farkle, not an essential.



Agreed, the extra wiring carrying all the electrical load is a potential problem area but as long as it`s been done with the correct gauge wire, secured properly and you avoid stresses due to flexing etc it`ll be fine.

If a fault ever did happen it`d be an easy fix to bypass the ammeter wiring and hook it back up to STD just by replacing the fuse (if the bike wasn`t on fire by that point!).
 

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Battery Bug

The best voltmeter plus that I've tried.
 

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I agree that an ameter can be usefull (as you stated you have a bidirectional centered one), but compared to a voltmeter its value is limited. What i mean is if you are going to have one of the two, the voltmeter wins hands down, but there is nothing wrong with having both.



As for the ameter itself, if it doesnt have an external shunt, then the shunt is inside the case. ALL ameters have them as the meter coils are usually something thin like #30 magnet wire, which is probably good for 1/4 amp before becoming a fuse. I have in the past "opened up" ameters to take the shunt out and put somewhere else just for the purpose of not having to run heavey wire (like in this case mounting the shunt in the power wire and ruinning 2 small guage wires to the meter).



I myself though about adding one (along with the volt meter) but for what it shows you I found it unnessissary. Charging voltage will tell you if everything is ok, where as current varies, and apart from showing "battery drain" doesnt really tell you much usefull. Anyway, I have rambled on enough lol
 
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