electrical issues

[gstallons]

Run your ground up to one of the ignition coil mounting bracket nuts located above the oil cooler.

[Kiwi_Roy]

Okay, located a ground wire that goes from the regulator mounting bolt and feeds into the wiring harness leading under the tank, along the frame and at that point I loose it. I don't want to take all that apart right now with a full tank. Can somone tell me specifically if they know where the regulator is typically grounded by the factory. Cause it seems awful strange to run the ground wire the full length of the motorcycle.

Yes, the original ground wire is shown going back to the battery, this wire is next to useless, it's way too small for the 30+ Amp pulses the alternator puts out.

Usually the regulator gets grounded by accident to the horn bracket then from horn bracket to chassis.

 

Look at the big red wire from the regulator, that same current has to come back through the ground.

Any Voltage loss between the battery negative and the regulator case is subtracted from the charge Voltage because the regulator doesn't care what the battery is, it just sets the Voltage between it's black wire to it's case at ~13.8.

From your low Voltage readings in a previous post I think you will notice a big difference in your battery Voltage with a proper ground.

All you need is about 8" of #14 wire from a regulator mounting bolt to a timing cover screw or as gstallions says the coil mount. Scrape the metal of the regulator to get a good contact and apply a little grease to stop it corroding.

Less than a 1 beer job

 

BTW, going back through the engine is less resistance than running a wire back direct.

[gstallons]

I use shakeproof (star) washers on any ground connection..... After many bad experiences I use them EVERY time.

[df2]

Okay, located a ground wire that goes from the regulator mounting bolt and feeds into the wiring harness leading under the tank, along the frame and at that point I loose it. I don't want to take all that apart right now with a full tank. Can somone tell me specifically if they know where the regulator is typically grounded by the factory. Cause it seems awful strange to run the ground wire the full length of the motorcycle.

Yes, the original ground wire is shown going back to the battery, this wire is next to useless, it's way too small for the 30+ Amp pulses the alternator puts out.

Usually the regulator gets grounded by accident to the horn bracket then from horn bracket to chassis.

 

Look at the big red wire from the regulator, that same current has to come back through the ground.

Any Voltage loss between the battery negative and the regulator case is subtracted from the charge Voltage because the regulator doesn't care what the battery is, it just sets the Voltage between it's black wire to it's case at ~13.8.

From your low Voltage readings in a previous post I think you will notice a big difference in your battery Voltage with a proper ground.

All you need is about 8" of #14 wire from a regulator mounting bolt to a timing cover screw or as gstallions says the coil mount. Scrape the metal of the regulator to get a good contact and apply a little grease to stop it corroding.

Less than a 1 beer job

 

BTW, going back through the engine is less resistance than running a wire back direct.

 

 

Can I run a ground wire in addition to the one that is already there, or do I need to remove the existing one?

[jrt]

I used a timing cover bolt as ground point. It's easy to get to. While you are at it, run a ground from the triple trees to the engine. I think the original ground path of the headlight goes through the steering head bearing

[Kiwi_Roy]

Can I run a ground wire in addition to the one that is already there, or do I need to remove the existing one?

 

That's your choice, I just left mine in place.

Most of the current will travel from battery negative thru the main fat ground wire to the chassis, thru the engine (aluminium is a very good conductor) to your new strap and to the regulator case.

 

How the Regulator works

Inside the regulator are 2 diodes between the yellow alternator wires and the red wire that goes to the battery and 2 SCRs (Silicon Controlled Rectifiers) connected between the case and the yellow wires.

Each time one of the yellow wires goes Positive the current passes thru one of the diodes to the battery + terminal. From the battery - terminal the current passes back thru the chassis to the regulator case then thru one of the SCRs back to the other alternator yellow wire.

When the regulator thinks the battery Voltage is high enough it just stops turning on the SCRs

This all happens 14 times for each revolution of the motor. If you were able to watch the current flow you would see it as a series of half wave pulses with gaps every now and then where the regulator decides the Voltage is high enough.

 

A schematic I drew when I had mine apart

Regulator Schematic - With Notes.pdf

[gstallons]

Kiwi,

Could diodes be added to the two remaining legs of the stator to make them work in the charging system ? Is it stated anywhere if this a Y or Delta wound stator? Just curious.......

[df2]

I used a timing cover bolt as ground point. It's easy to get to. While you are at it, run a ground from the triple trees to the engine. I think the original ground path of the headlight goes through the steering head bearing

 

 

I believe there is one already. I didn't get the chance to follow it to it's source so it's either the Triple or right out of the instrument panel going to one of the timing cover bolts. In fact it was a bit frayed at the timing bolt and might be part of the issue with my instrument panel. I will check it closely when I am home.

[jrt]

I believe there is one already. I didn't get the chance to follow it to it's source so it's either the Triple or right out of the instrument panel going to one of the timing cover bolts. In fact it was a bit frayed at the timing bolt and might be part of the issue with my instrument panel. I will check it closely when I am home.

 

Cool- but definitely check the source.

If the wire is frayed, then just trim it back and crimp on a new connector.

Hope this works out better for you than the thread I've been following on the Ducati forum. Poor fellow wired his battery in backwards and fried his $500 ECU.

J

[Kiwi_Roy]

Kiwi,

Could diodes be added to the two remaining legs of the stator to make them work in the charging system ? Is it stated anywhere if this a Y or Delta wound stator? Just curious.......

 

My alternator only has two wires, I'm not sure what you mean by 2 remaining legs. It works with a full wave bridge rectifier consisting of 4 diodes it's just that two of them are controlled. See the drawing I attached a few posts back.

 

It's neither, Y or Delta refer to a 3 phase winding as most bikes and cars have.

The Guzzi is a single phase 7 pole alternator (7 pairs that is).

 

Roy

[gstallons]

Ok....thank you.

[df2]

Okay, ran new #14 wire from regulator to timing cover bolt. Done. Did see that the other ground coming from up somewhere around the instrument panel was frayed and put a new waterproof crimp and seal connector on it. Done. Re-adheasved the ecu back down and reconnected its ground. Now to figure out why my instrument panel light for tach and speedo don't work. The good news is that idiot lights are back.

[jrt]

 

For ground wires, you needn't worry too much about making them weatherproof. They carry ground, after all.

Keep in mind the color scheme for wires also. Don't run a ground through red wire or (worse) a hot wire through black. Might not matter now, but if anyone else works on the bike, they could be in for a shock. (ha ha, I'll be here all week....try the veal)

[gstallons]

A ground wire is equally important as a positive wire..... As corrosive as the junk that is applied to road surfaces in the winter now the connector he talked about using is the best. The road "salt" used now can destroy a 22 ga wire in 3 yrs that has the insulation cut back or opened up.

[df2]

I used black as all the other grounds on the bike are black (I always thought they were green) but considering the wire runs from mounting bolt to timing bolt, I think anyone else will get that it is ground, but I do get your point, especially on hot wires as it makes sense to stick with the wiring diagram key.

 

So next question, where is the neutral switch located?

 

PS. every time you guys mention a part, I go to manual to figure out what it looks like and where it is. You might as well say the thingy next to the whatmamachalit. I'm not that bad

but I did mix up the regulator with ecu....

 

But thanks for all your help, each of you!