Voltmeter for 1st Gen Vmax

[jeffwat]

I’m about to wire in an upgrade rectifier/regulator(R/R) in my 1989 Vmax. My stators fine,(checked), but I’ve been left a couple times on the street, with dead battery, dead R/R.

I’d very recently wired a voltmeter into headlights, mounted on handlebar bracket, but found it reads 0.5-0.8 volts low, and disconnects during startup (headlight relay cutout).

So, had to get more creative. I bought a single pole 12 volt relay. They cost about 7-8 dollars at auto parts. Standard configuration is terminal numbers 85 and 86 for the relay coil, 30 for switch inlet voltage, and 87 for switch activated outlet.

Brown (+) wires go everywhere out of the ignition switch, fused. I found an easy brown wire tie-in for my new relay coil on the thermostat fan switch on the right side, under the thermostat (brown wire). Under right fake air scoop. I used a 3 way connector to splice into the brown wire. I ran this new brown wire around the back of the air cleaner to the left side, attached to new relay terminal 85, physically fastening said relay to the middle plastic electronic box ( under left fake air scoop).

I’ve had a trickle charge connection for years, directly connected to the battery, with the plug-in on the left side of the bike, right by the California carbon canister under the front of the seat. I tapped into that for the ground connection, running a black 14 gage wire over to the new relay (coil only draws 0.1 amps), terminal 86.

For the voltmeter, I ran a red (positive) 14 gage wire from my trickle red connection to new relay terminal 30, and connected the voltmeter positive red wire to new relay terminal 87. I split and tied the same trickle connection ground (-) wire into the voltmeter negative black wire.

I zip tied all wires neatly, used liquid electrical tape on all connections, followed by regular electrical tape.

So, when I turn on the ignition switch, new relay coil closes, connecting terminal 30 to 87, and I see actual voltage at the battery (validated with separate voltmeter).

It works great. I like that I can see voltage level during cranking, and an accurate voltage. I’m now ready to pursue a new R/R upgrade.

It’s simpler than all the words sound.

Jeff

 

[Bill Seward]

I've run a voltmeter on my '85 for years.. I ran the wires to ground and a fuse that is switched on with the key. I use a copy of the Kuryakyn unit, got it on Fleabay for around $12. It always reads 3 greens when the engine is running. The Kury unit is pictured here, but the copy looks identical. Got it mounted to the handlebar clamp.

 

[jeffwat]

Thanks Bill. I have one of those for years also, like you on handlebar, but hooked into headlights. It read one green bar. I decided to go voltmeter, I like the numbers. I couldn’t find a good connect back then, whether it existed or not. While I’m done, and it works great, could you tell me exactly where you hooked it in.

As a retired engineer, I guess I just like relays.

Thanks for early response.

Jeff

 

[Bill Seward]

I took off the faux tank, and checked the fuses with my meter till I found one that switched on with the key. I simply stripped a bit of insulation off the really thin wire and wrapped it tightly around one blade of the fuse, and stuck it back in place. I grounded it to one of the ground points near the fuel pump. I have a meter on my Roadstar, and got the power from the brake light switch on the handlebar.

I agree with you about relays. My headlights are relayed, and I wired a new relay into the circuit for the Roadstars fuel pump. I've got 100 watt H4 bulbs in my Kia Soul, those are relayed also.

I've got a high output Venture stator in the bike, along with an SH775 series regulator, and the bikes charging system works great. I'm reading over 14 volts at the battery with my digital voltmeter.

 

[jeffwat]

Thanks, should have searched with voltmeter as you did, but I’m happy.

I love my Vmax, but not the small tank. Many years ago, almost bought the Venture Royale, but just as I was ready, they stopped making. It’s a great bike, but back then wanted to buy new.

Jeff