Topic: Voltmeters for Bikes?

[burmashave]

In another thread about electrics, we got into a discussion about on board voltmeters for bikes. We were wondering what experiences others have had.

I've tried two: the Kuryakyn L.E.D. Battery Gauge and the Signal Dynamics LED Gauge

Kuryakyn L.E.D. Battery Gauge
This is the one I'm using now. I wired the positive into the ignition switched voltage, and the negative runs directly to the battery. I mounted it below the instrument lights:



Pros:
I like the looks of it, and it mounts where it doesn't spoil the classic look of the bike. The gauge reads out in color (yellow LED's below 13V, green 13-14V, and red above 15V). It seems to be waterproof although I haven't had it in a downpour.

Cons:
It's not precise in that it reads out only in increments of a single volt.  It reads low (mebbe 1/2 volt); however, I'm guessing that this is a function of not wiring it directly to the battery.

Signal Dynamics LED Gauge
The Signal Dynamics Gauge is not so much a gauge as it is a "smart" dummy light. I tried this one first. I mounted mine to the left of the start/stop switch on the bottom of the bars. This allowed me to easily see it, while making it hidden for the most part.



Essentially, it has 5 states: Flashing Green (15.25V+), Steady Green (12.9V+), Steady Amber (12.6V+), Steady Red (12.1V+), Flashing Red (12.1V-).

Pros: Might be O.K. if you just want a warning light for negative charging states. It's easily hidden.

Cons: It really doesn't provide much information. Also, I seemed to be always in the flashing red status (partly because it read low), and it's annoying to have the stupid thing flash at you for long periods of time.

A Different and Cool Option
About a year ago, a headlight bucket with a voltage meter appeared on ebay. I think one of the members here either picked it up or asked about mounting it. The bucket had come off a pre-SOHC/4 bike, but it was way cool. The voltage meter was small and was recessed into the top of the bucket. You might be able to put a voltmeter in the top of an SOHC/4 bucket, but mebbe it would be hard to replicate the old school look.

[TomC]

Hi Burnashave
     You would think with all the electrical problem threads on here that this would be a HOT topic.
     I am currently experimenting with voltage regulation on my CB400F1. So I have a digital voltmeter wired across my battery and a analog voltmeter across my field. Some what of a mess. The digital is not at all water proof. The analog does not seen to be bothered by a little water. My thought is a clear plastic box with a hole in the bottom for the leads to keep the meters dry. But my digital voltmeter needs to be turned off which would be a problem.
     I guess that the LED voltmeters would be OK if the voltage ranges were better. I would like to know, below 12V, 12V to 13.5V, above 13.5, below 15V. But I am too use to seeing the voltage change by the hundredth of a volt.
     TomC in Ohio

[troppo]

I`ll have to look into a small mechanical volt meter like you`d find in the dash of an older car, may even be able to find a digital readout unit.
If i was an electronic wizz i`m sure i could come up with a small digital unit (any electronic wizards out there? lol)

[burmashave]

If i was an electronic wizz i`m sure i could come up with a small digital unit (any electronic wizards out there? lol)

I think that'd be a good way to go--a three digit LED. It'd be small and precise. As for accuracy, it'd be nice if you could adjust it for a standard error, as happens when connecting it to an ignition source as opposed to directly to the battery.

[burmashave]

A somewhat quick search turned up a few items:

This Article from another forum details a few options. Apparently, some of the 3 1/2 digit LED voltmeters on From Datel on this Page are sealed in epoxy and possibly waterproof (or water resistant).


It's about $70. The one I looked at is about 1" deep, so I don't know how good it'd be for a surface mount. This seems to be a problem with most units I've seen. They are designed for a dash mount, so they turn out to be deep.

The FAQ writer claims that LED displays may "cook" if exposed to the sunlight.

A company called Lascar produces This Round Waterproof/Water Resistant 4 1/2 LED Display for marine use:



It is also about 1" deep. It's about $60. Personally, I'm not fond of the looks.

The back of these would need to be epoxied to waterproof them. I'm wondering if the front of an LED display could be waterproofed (with epoxy?) and still be easily readable. If so, then it becomes a matter of creating a small voltmeter module that could sit in the headlight bucket. The module could then be connected to the "waterproofed" LED.

Personally, I would trust a unit well sealed in epoxy over the commercial units I've seen.

[TomC]

Hi Fellow Volt Measurers
     "The FAQ writer claims that LED displays may "cook" if exposed to the sunlight."
     I have had this happen with my digital voltmeter. But it has always come back when it cooled off. Also after being rained on it returned to working after about three days. I have had similar experiences with an LCD watch.
     I wonder if a brand new 9V battery is usable as a voltage standard for checking voltmeters? I check my voltmeters with each other. They all get within 0.10 volts of each other. But how close are they to correct?
     My Harbor Freight Tools flier came today. "7 Function Digital Multitester" Lot no.90899/98025 $2.99
          TomC in Ohio

[dusterdude]

autometer