2001 V11 sport charging issues ?

[dsrdave]

I was out for a ride today and the charge light came on, the tach started reading low, often at zero.  I assume the tach issue is due to low voltage.  I've never had charging issues on a spiny.  Is there any common problems?
Thx, Dave

[LowRyter]

mine was overcharging.  A new VR is about $100

[dsrdave]

I measured voltage when running and had 11.88.  So not over charging....

[guzzisteve]

I would be checking AC voltage at yellow wires.

[kingoffleece]

11.88 sounds way too low.

[dsrdave]

Thx, Steve.  Nothing coming from the alternator. 

[Murray]

Thx, Steve.  Nothing coming from the alternator.

Just checking you did test on AC between the two wire?

[Kiwi_Roy]

It's the flakey way they sense the battery Voltage on that particular model.
A normally closed Start Relay contact turns on the Headlight Relay which of course turns on the headlight but also powers up the tach and provides the power and Voltage reference to make the regulator work. If it was at night you would notice the lights failing also.
Just know that any time you see the tach acting up chances are you might be pushing when the battery goes flat, my first Guzzi was a 2001 VII Sport so I know of what I speak.

This wiring scheme can also lead to over-charging, if the voltage drops just a little the regulator senses the battery is going flat (even if its over 15V) and cranks up the charge rate cooking the battery or itself.

The fault probably lies in either of the first two relays, change those out and see what happens.

I eventually changed my regulator for a direct connected Electrosport, this cured charging but not without a new problem, residual current draw which meant I had to disconnect it over the winter months.
BTW, your 2001 should never suffer from Startus Interuptus, the starter is wired the way all Guzzis should be.

[dsrdave]

Yes, the two leads coming from the alternator were tested on A/C.  With zero output.

[Chuck in Indiana]

Yes, the two leads coming from the alternator were tested on A/C.  With zero output.

Well, that kinda narrows it down.. 

[Kiwi_Roy]

One of the wires on mine snapped off where soldered to the coils. I had to replace the wire as it was too corroded to solder back on.
But that doesn't account for the tach playing up, it's really supplied from the battery.

[Chuck in Indiana]

One of the wires on mine snapped off where soldered to the coils. I had to replace the wire as it was too corroded to solder back on.
But that doesn't account for the tach playing up, it's really supplied from the battery.

For whatever reason, when the voltage gets too low, the tach goes nuts.. BTDT. 

[Kiwi_Roy]

The battery will certainly get low if a yellow wire is broken.
Followed a short time later by the engine cutting out.