Mounting Voltmeter - 2003 EV

[SemperVee]

If you were to install a round digital volt meter & cell charging port up off the HB risers as fashioned  - where would you recommend tapping into access switched power and ground? Inquiring minds need to know?  Thanks. . .  Thinking off the blinker connection or heated grips maybe?

[Kiwi_Roy]

I'm guessing a 98 EV, actually it doesn't make much difference
https://www.thisoldtractor.com/guzzi007/schematics/2004_EV_Catalytic.gif
Electrically you want the connection as close to the battery as possible to avoid any Voltage drop.
i would even consider adding a small 12 Volt relay to feed the meter direct from battery
the relay coil can be from anywhere on the ignition circuit as the coil can handle some loss in Voltage.
On later models like my 2017 V7III I connect the Voltmeter across the small running light in the headlight bucket, that circuit only has a small load on it
As for mounting the meter bracket, look at the Bar clamp you might find the two halves are separated by a small gap.
I use a bracket from 18 Gauge Aluminium sheet, it fits nicely in the gap, loosen the clamp insert the bracket then tighten the two front bolts to clamp the bracket the two rear bolts are tightened last to clamp the bars.
you might want to put the bracket behind the bars if you have more room to clear the tank.
Use a step drill to make the hole in the bracket.

[SemperVee]

I'm guessing a 98 EV

Hi Roy,  My mistake; 2003 EV

[73 sport]

      Wiring on Italian bikes is usually under capacity. I would run a 14ga , preferably 12ga, to the battery with a fuse in the line.

[nc43bsa]

      Wiring on Italian bikes is usually under capacity. I would run a 14ga , preferably 12ga, to the battery with a fuse in the line.

I think that's a little overboard for a USB port.

[SemperVee]

I'm guessing a 98 EV, actually it doesn't make much difference
https://www.thisoldtractor.com/guzzi007/schematics/2004_EV_Catalytic.gif
Electrically you want the connection as close to the battery as possible to avoid any Voltage drop.
i would even consider adding a small 12 Volt relay to feed the meter direct from battery
the relay coil can be from anywhere on the ignition circuit as the coil can handle some loss in Voltage.
On later models like my 2017 V7III I connect the Voltmeter across the small running light in the headlight bucket, that circuit only has a small load on it
As for mounting the meter bracket, look at the Bar clamp you might find the two halves are separated by a small gap.
I use a bracket from 18 Gauge Aluminium sheet, it fits nicely in the gap, loosen the clamp insert the bracket then tighten the two front bolts to clamp the bracket the two rear bolts are tightened last to clamp the bars.
you might want to put the bracket behind the bars if you have more room to clear the tank.
Use a step drill to make the hole in the bracket.

I like your idea Roy of using the headlight bucket and tapping the small switched wire to running headlight and either adding a relay or perhaps a small inline fuse but the draw fom the digital meter is very light and only 5 watts for the cell phone if needed.  You can see I already have a bracket mated to the volt meter. Thanks!

[Wayne Orwig]

I wired mine on my 2004 EV into the 'city bulb' in the headlight bucket. Easy to do and switched with the key.

The advantage, or disadvantage, is that there IS a voltage drop due to all of the loads on that line. It reads a few tenths of a volt low. Not a problem. One day it started reading a good bit low. It turns out there was a problem with the relay in that circuit, and the voltage drop pointed it out.

Sometimes it is good to test the entire system and not directly connect to the battery where you may not see problems cropping up.

[SemperVee]

I wired mine on my 2004 EV into the 'city bulb' in the headlight bucket. Easy to do and switched with the key.

The advantage, or disadvantage, is that there IS a voltage drop due to all of the loads on that line. It reads a few tenths of a volt low. Not a problem. One day it started reading a good bit low. It turns out there was a problem with the relay in that circuit, and the voltage drop pointed it out.

Sometimes it is good to test the entire system and not directly connect to the battery where you may not see problems cropping up.

Wayne,  might you have a picture to show your handiwork with the connections?  Thanks.

[John Croucher]

I have the same type, but with on/off switch.  Wired directly to battery.

[Wayne Orwig]

Wayne,  might you have a picture to show your handiwork with the connections?  Thanks.

No. It is just the little bulb below the main headlight bulb. Pull the headlight shell and it is obvious.

[Kiwi_Roy]

I wired mine on my 2004 EV into the 'city bulb' in the headlight bucket. Easy to do and switched with the key.

The advantage, or disadvantage, is that there IS a voltage drop due to all of the loads on that line. It reads a few tenths of a volt low. Not a problem. One day it started reading a good bit low. It turns out there was a problem with the relay in that circuit, and the voltage drop pointed it out.

Sometimes it is good to test the entire system and not directly connect to the battery where you may not see problems cropping up.

As Wayne says, this is how I wired my V7iii Special
I see 12.5 after the bike has been sitting for a week and up to 14.1 at speed.

[Perazzimx14]

While the volt meter is better right off the battery I don't get too concerned with that and usually tap the wiring anywhere convenient that is on keyed power. Honestly I don't care about the exact voltage I want to see how the voltage is reacting. Constant, falling or rising. I mainly use the volt meter to monitor the batteries state of charge when running heated gear on bikes that do not have a lot of additional electrical capacity.

Most bikes will keep up with the additional electrical load at speed but fall short at low speed and/or idling. I can watch the volt meter and if it starts dropping below what is normally displayed I toggle off the heated gear and watch the charging system replenish the battery.

[SemperVee]

While the volt meter is better right off the battery I don't get too concerned with that and usually tap the wiring anywhere convenient that is on keyed power. Honestly I don't care about the exact voltage I want to see how the voltage is reacting. Constant, falling or rising. I mainly use the volt meter to monitor the batteries state of charge when running heated gear on bikes that do not have a lot of additional electrical capacity.

Most bikes will keep up with the additional electrical load at speed but fall short at low speed and/or idling. I can watch the volt meter and if it starts dropping below what is normally displayed I toggle off the heated gear and watch the charging system replenish the battery.

That makes a lot of sense.  Don't try and confuse us with logic now....

[SemperVee]

I wired mine on my 2004 EV into the 'city bulb' in the headlight bucket. Easy to do and switched with the key.

The advantage, or disadvantage, is that there IS a voltage drop due to all of the loads on that line. It reads a few tenths of a volt low. Not a problem. One day it started reading a good bit low. It turns out there was a problem with the relay in that circuit, and the voltage drop pointed it out.

Sometimes it is good to test the entire system and not directly connect to the battery where you may not see problems cropping up.

Wayne,  I looked inside and my question to you is did you tap directly on the wires feeding the small running headlight both power+ AND  ground-  inside the headlight shell? Thanks!