Author Topic: Voltmeter  (Read 823 times)

Offline Kiwi_Roy

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Voltmeter
« on: June 17, 2025, 01:56:53 PM »
When I first bought my V7III it had a bad alternator winding which was unable to keep the battery charged. It was replaced under warranty

Now I have a cheap round 2 wire Voltmeter on my Guzzi
Its always on when the key is on, wired to the headlight bucket across the Park Light where there is only a tiny load.
Takes away the worry of, "Is the charging system working?"
I like the Blue LED model, I think it shows up better than the other colours.

https://www.amazon.ca/Waterproof-Voltage-Digital-Voltmeter-Motorcycle/dp/B09MZHJQJX/ref=asc_df_B09MZHJQJX?

I have it mounted on a 18 gauge aluminium bracket that is pinched between the bar clamps
Usually when I turn on the bike it reads ~12.5 Volts and drops down to ~ 10 while cranking then pops up to over 12. I sometimes see 14 Volts riding at speed.
I highly recommend having a Voltmeter, takes away the worry
I drilled the large hole for mounting using a step drill.
https://www.amazon.ca/Waterproof-Voltage-Digital-Voltmeter-Motorcycle/dp/B09MZHJQJX/ref=asc_df_B09MZHJQJX?

Might I suggest you make a group purchase to reduce the cost of shipping.
« Last Edit: June 17, 2025, 06:28:53 PM by Kiwi_Roy »
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Offline DoubleGuzzi

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Re: Voltmeter
« Reply #1 on: June 17, 2025, 04:39:02 PM »
You can strip all that tracking garb from the URL, from the question mark onwards.  :wink:

I also prefer blue but use the much smaller oblong ones and attach direct to battery, so as to be able to monitor levels during Winter layoffs.
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline Kiwi_Roy

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Re: Voltmeter
« Reply #2 on: June 17, 2025, 06:07:39 PM »
You can strip all that tracking garb from the URL, from the question mark onwards.  :wink:

I also prefer blue but use the much smaller oblong ones and attach direct to battery, so as to be able to monitor levels during Winter layoffs.


https://www.amazon.ca/Waterproof-Voltage-Digital-Voltmeter-Motorcycle/dp/B09MZHJQJX/ref=asc_df_B09MZHJQJX?

Thanks for that information
Roy
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Online AJ Huff

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Re: Voltmeter
« Reply #3 on: June 17, 2025, 06:25:29 PM »
This appears to be the same thing but available in the US from Amazon.

https://a.co/d/2U3B4JJ

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Offline Kiwi_Roy

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Re: Voltmeter
« Reply #4 on: June 17, 2025, 06:31:23 PM »
This appears to be the same thing but available in the US from Amazon.

https://a.co/d/2U3B4JJ

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Yes but more than twice the price $14 against $6
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Offline DoubleGuzzi

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Re: Voltmeter
« Reply #5 on: June 17, 2025, 08:13:13 PM »
« Last Edit: June 17, 2025, 08:15:48 PM by DoubleGuzzi »
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Online ridingron

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Re: Voltmeter
« Reply #6 on: June 17, 2025, 09:16:48 PM »
Yes but more than twice the price $14 against $6

One has free shipping while the other doesn't. Look for the total price and shipping time.

Old Probverb: You always pay for what you get but you don't always get what you pay for.

Offline Kiwi_Roy

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Re: Voltmeter
« Reply #7 on: June 17, 2025, 10:29:03 PM »
[quote author=DoubleGuzzi

I also prefer blue but use the much smaller oblong ones and attach direct to battery, so as to be able to monitor levels during Winter layoffs.

[/quote]
Do you mean the Voltmeter is displaying 24/7?
I have mine connected to the Park light circuit, its only on when the key is On, the circuit is lightly loaded, just the tail light and an LED in the Park light.
When I turn the key On the pump primes of course and the light display with full scale travel of the clocks.
Reads about 12.4 Volts
Drops down to just over 10 while cranking over then a few seconds later is over 13 with engine idling, can rise to 14.1 at 3,000 RPM
I recently modified mine with a tube to shield the display so its visible in bright sun.
« Last Edit: June 17, 2025, 10:47:37 PM by Kiwi_Roy »
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Offline DoubleGuzzi

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Re: Voltmeter
« Reply #8 on: June 18, 2025, 03:44:44 AM »
Do you mean the Voltmeter is displaying 24/7?
Nah, that would need two batteries in series.  :evil:
Seriously though.. yes, given that most bikes have some parasitic draw anyway (particularly modern bikes), then a high resistance voltmeter isn't going to add a significant amount. The spec. says working current: <30mA though I haven't actually measured this. Older/cheaper bike alarms have a similar drain.
Each to their own but I prefer to monitor battery terminal voltage, rather than some circuit that has been influenced by components and wiring harness. The other relevant place for the voltmeter is across the rectifier/regulator output, should you not want the display to be permanently showing.

BTW, mine are affixed using bath edging sealant, 'cos I'm too lazy to fabricate an aluminium or steel bracket. I should really chop off the fitting tangs though sometimes I loop a cable tie through one, for peace of mind.

« Last Edit: June 18, 2025, 03:51:46 AM by DoubleGuzzi »
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline sign216

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Re: Voltmeter
« Reply #9 on: June 18, 2025, 07:29:31 AM »
I added an "edgewise" meter to the dash of my '09 V7 Classic.  Saved my butt a few years ago, when the erratic reading clued me of a problem.  Turned out it was the 4-way connector under the fuel tank, a known issue of this V7 model.

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Offline Wayne Orwig

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Re: Voltmeter
« Reply #10 on: June 18, 2025, 08:00:23 AM »
Seriously though.. yes, given that most bikes have some parasitic draw anyway (particularly modern bikes), then a high resistance voltmeter isn't going to add a significant amount. The spec. says working current: <30mA though I haven't actually measured this. Older/cheaper bike alarms have a similar drain.

With the LEDs on?

30ma load on a battery that is maybe 15Ah. (maybe a bit more, but still..)
That is 500 hours. Or 21 days. And lead batteries should never be drained below about 50% or they will start to sulfate. So, you need to charge it every 10 days to prevent battery damage.
I would put a switch on it or find an LCD meter.
Scientist have discovered that people will believe anything, if you first say "Scientists have discovered...."

Offline DoubleGuzzi

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Re: Voltmeter
« Reply #11 on: June 18, 2025, 08:06:44 AM »
I added an "edgewise" meter ..
The scale leaves a little bit to be desired, IMHO ; >14.8V is a red zone in my book. If it served/serves a purpose, then all good. You didn't say where you connect it to.
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline DoubleGuzzi

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Re: Voltmeter
« Reply #12 on: June 18, 2025, 08:16:57 AM »
With the LEDs on?
If they ain't on then it ain't working!  :huh: If I remember, I'll measure the actual current consumed.

30ma load on a battery that is maybe 15Ah. .. I would put a switch on it or find an LCD meter.
Your points are valid; I'd suggest a momentary on switch, should this be a worry, though wouldn't allow constant monitoring. I use 'smart' chargers, therefore it isn't really of concern to me.

[Edit]
Current draw when measured, at an approx. ambient temperature of 20degC and one minute on time: 7mA
IIRC different colours consume different current draw and I noted current increase, as the voltmeter remained on, presumably getting warmer.
« Last Edit: June 18, 2025, 10:26:28 AM by DoubleGuzzi »
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline kingoffleece

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Re: Voltmeter
« Reply #13 on: June 18, 2025, 11:52:19 AM »
I just plug a small meter into my SAE tender lead.  Check it a few times during the ride.  Yes, it's not a constant read-out but it's easy to check at a stop.

https://www.amazon.com/battery-tender-081-0157-disconnect-voltage/dp/b00dj5ke9a
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Offline DoubleGuzzi

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Re: Voltmeter
« Reply #14 on: June 18, 2025, 12:40:00 PM »
I just plug a small meter into my SAE tender lead..
A reasonable option/compromise though considerably more expensive.
An SAE extension lead up to the front end, might be a cunning plan. Attach the meter with say, hook & loop, should you want to remove it for security. Just a thought.
« Last Edit: June 18, 2025, 12:49:09 PM by DoubleGuzzi »
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline kingoffleece

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Re: Voltmeter
« Reply #15 on: June 18, 2025, 04:30:25 PM »
I've done that when monitoring a charging system.  Once I know it's good spot check is all that is necessary.

More expensive?  Yep.  But I move it to 6 different vehicles, so there's that...............
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Offline Wayne Orwig

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Re: Voltmeter
« Reply #16 on: June 18, 2025, 06:04:37 PM »
Google "battery monitor BM2".
You attach that little box to the battery. You can check the battery voltage any time on your phone. The real advantage is that it records it non-stop.
After a ride, you have a record of the charge voltage. Connect a trickle charger, you have it on record. Stopped at a red light versus high rpm, you have a record.
Handy little thing.
Scientist have discovered that people will believe anything, if you first say "Scientists have discovered...."

Offline DoubleGuzzi

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Re: Voltmeter
« Reply #17 on: June 18, 2025, 06:45:53 PM »
You lot are a bad influence, especially kingoffleece!
Was too cheap not to buy:
https://www.ebay.co.uk/itm/316780686372

Totally OTT for me, as I use a mobile phone only for texting and a rare phone call - strange, eh? Makes for a simple mounting options though but is substantially bigger and in-yer-face.
 :rolleyes:
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline elrealistico

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Re: Voltmeter
« Reply #18 on: June 18, 2025, 07:01:15 PM »
I have something similar. with blue LEDs. Easy to mount, not permanent and has an on off switch. I use it on long rides with a cable to my phone in my jacket pocket to charge the phone. I use Beeline for navigation on long trips, and it uses the phone GPS via BT, so it can suck down the juice. I also have a super cheapo Amazon LED voltmeter on the T140, connected to switched battery power in the nacelle, and velcro'd to the steering bearing cover


You lot are a bad influence, especially kingoffleece!
Was too cheap not to buy:
https://www.ebay.co.uk/itm/316780686372

Totally OTT for me, as I use a mobile phone only for texting and a rare phone call - strange, eh? Makes for a simple mounting options though but is substantially bigger and in-yer-face.
 :rolleyes:
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Offline Vagrant

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Re: Voltmeter
« Reply #19 on: June 19, 2025, 08:42:41 AM »
Just FYI. I bought one of those a few years ago for my 2016 V7II. The vibration killed it in about 2000 miles. Both USB ports, left the ship!
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Offline Kiwi_Roy

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Re: Voltmeter
« Reply #20 on: June 25, 2025, 09:34:49 AM »
Slightly off topic, I ordered one of these a while back, it came yesterday, excellent value
The upper display shows charging current, lower shows Voltage (just over 5 Volts)

https://www.temu.com/ca/usb-charger--current-voltage-charging-detector-battery-voltmeter-ammeter-multimeter-usb-tester-mobile--monitor-g-601099575493927.html

Charge two loads at once from one adapter Phone, wireless mouse wireless keyboard etc.
« Last Edit: June 25, 2025, 10:58:50 PM by Kiwi_Roy »
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Offline DoubleGuzzi

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Re: Voltmeter
« Reply #21 on: June 25, 2025, 11:02:01 AM »
^ remove the question mark at the end of the URL.  :wink: Otherwise, one gets asked to login.  :violent1:
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline SemperVee

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Re: Voltmeter
« Reply #22 on: June 25, 2025, 11:04:17 AM »
 Or use this as I do for checking at under the seat 12PP on the Norge or any other vehicle pp.


« Last Edit: June 25, 2025, 11:06:43 AM by SemperVee »
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Offline DoubleGuzzi

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Re: Voltmeter
« Reply #23 on: June 25, 2025, 05:04:51 PM »
Or use this as I do for checking at under the seat 12PP on the Norge or any other vehicle pp.
Kinda tricky to see, at 70mph.  :huh:
Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline Perazzimx14

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Re: Voltmeter
« Reply #24 on: June 26, 2025, 09:19:48 AM »
I put a LED volt meter on the Buell and at idle its hard to read as the bike virbrates at a slight different frequency making the LED readout look like its moving around when the bike is idling.
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Offline Kiwi_Roy

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Re: Voltmeter
« Reply #25 on: June 26, 2025, 10:25:32 AM »
Google "battery monitor BM2".
You attach that little box to the battery. You can check the battery voltage any time on your phone. The real advantage is that it records it non-stop.
After a ride, you have a record of the charge voltage. Connect a trickle charger, you have it on record. Stopped at a red light versus high rpm, you have a record.
Handy little thing.

Is this the one you have Wayne?
https://www.amazon.ca/anmas-rucci-Battery-Monitor-Bluetooth/dp/B08F9T4QC5/ref=asc_df_B08F9T4QC5?
I watched the video and one thing I don't quite understand. How does the Bluetooth signal get out of the steel enclosed engine compartment?
I have a Gerbing 2 channel blootooth  heat controller for my heated vest/gloves but the controller there is under the plastic side cover on the V7III in direct line of sight.
The first controller I bought failed on one channel (the Vest load was too much for it) so when I received the replacement I added a tiny cooling fan to keep it cool.
« Last Edit: June 26, 2025, 10:50:32 AM by Kiwi_Roy »
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Offline DoubleGuzzi

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Re: Voltmeter
« Reply #26 on: June 26, 2025, 11:38:50 AM »
Another bike gets the small LED addition..


Nearly natural progression.. SS50, Z200, Z250B, Z400J, (H100), GT750, K100, ZR1100, 900 Trident, 955 Sprint ST, (ZR550, M600), 900 ST, (B750), V7III CS, (V50II).

Offline Wayne Orwig

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Re: Voltmeter
« Reply #27 on: June 26, 2025, 01:10:06 PM »
Is this the one you have Wayne?
https://www.amazon.ca/anmas-rucci-Battery-Monitor-Bluetooth/dp/B08F9T4QC5/ref=asc_df_B08F9T4QC5?
I watched the video and one thing I don't quite understand. How does the Bluetooth signal get out of the steel enclosed engine compartment?
I have a Gerbing 2 channel blootooth  heat controller for my heated vest/gloves but the controller there is under the plastic side cover on the V7III in direct line of sight.
The first controller I bought failed on one channel (the Vest load was too much for it) so when I received the replacement I added a tiny cooling fan to keep it cool.

That is it, but I got it cheaper. Maybe it was on fleabay. I bought a set of two for like $25 on Prime day a couple years back if I recall.
I have 4 of them. One for each bike, plus an RV, and my Miata. My Miata one is in the metal trunk and works from over 20 feet away.
They appear to record the voltage once a minute.


Just found this:
https://www.ebay.com/itm/177173569232?_trksid=p4481478.c101506.m1851
But there are shipping charges.


« Last Edit: June 26, 2025, 01:17:31 PM by Wayne Orwig »
Scientist have discovered that people will believe anything, if you first say "Scientists have discovered...."

Offline Kiwi_Roy

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Re: Voltmeter
« Reply #28 on: June 26, 2025, 03:49:50 PM »
That's very good Wayne but for my riding I'm quite happy with my cheap digital display the battery shouldn't discharge while the key is off and the alternator is now working properly.

Cheers
Roy
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