nylon screws

[pamcopete]

You guys are way over my head. Pamcopete can you turn me on to one of those magic relays you mentioned with hookup instructions? Are you guys saying what I have will work??? I was thinking I would want something like 12.5 volts at idle and 14.5 at high revs.
Pamcopete you were right The VOM was indicating .3ohms.

Two many... I have gone through cleaning all the wiring rear of the tree. Still ready to go after the headlight and handlebars.

Your goals of 12.5 and 14.5 are nominal, but where are you measuring? If you read my post you should understand that the battery voltage will always be higher than the brown wire regulated voltage at high revs, so at the battery you should add at least .5 Volt except at idle because at idle it's the reverse because the alternator is not contributing to the load, so you should expect 11.5 at the battery at idle due to the internal resistance of the battery and at least 15 Volts at high revs due to the loss across the ignition switch. If you are measuring at the brown wire, then these readings would be different by .5 Volt, or 11 at idle and 14.5 at high RPM

This low voltage at idle is also a problem because in your typical riding profile in town, you do a lot of stop and go, so when stopped the alternator is not contributing and in fact the regulator is at its maximum current output to the rotor and it gets this current from the battery. The headlight is the big current hog and when waiting at the red light, the headlight pulls the battery voltage down. When the light changes and you increase the revs, the alternator starts to contribute to the load and provide a paltry 2 Amps to charge the battery, so quite often the battery is not completely replenished due to gear shifting and the slower speeds in town, so as the day progresses, the battery ends up with a net deficit when you wheel it into the garage. The next morning you add to this deficit when you load the battery with the starter, so as the week progresses, the battery is barely breathing. This is why I recommend that you put the battery on a trickle charger overnight, every night.

However, on two of my bikes, including the '81/H, I have installed yet another magic relay that turns the headlight off when I shift into neutral at a stop light. This reduces the draw on the battery by half, so I stand a better chance of recharging the battery just from normal riding.

Here is a pic of the "magic" relay that I use for these mods.

These are available at most auto supply stores for about $5. You will need the 5 terminal type for the neutral headlight mod. You can use either the 5 terminal type or the 4 terminal for the regulator brown wire mod.

 

[wingman1946]

New numbers this morning. I did add a ground wire from the regulator case to the battery ground at the frame. Also got the idle rpm to slow down a bit more. I'm not used to a tac divided into 500 rpm increments. At 1100/1200 ??rpm I got 12.78 at the battery. 13.24 on the brown wire at the reg connector. 12.30 inner brush... .84 outer brush. 14.53 at 3000 rpm. After all readings battery was at 12.66
Pamcopete is there any chance to get a diagram to connect that magic relay?

 

[5twins]

I would be interested in this as well. Pete, I don't recall you ever mentioning this "magic relay" in any of your earlier posts or the reasons behind it? I understand it now and can see the benefit.

 

[wingman1946]

5twins how are those numbers looking this morning?

 

[5twins]

I'm really not an electrical guy so I'm afraid I can't tell you much. They look like Greek to me, lol. I do understand the broad picture but not so much when you get down to all these individual wire readings.

 

[wingman1946]

Me too.

 

[pamcopete]

The Magic relay:

This little mod will connect the regulator directly to the battery so the regulator will regulate the battery voltage instead of the load on the brown wire.

Some may argue that there is just as much potential for a voltage drop with this arrangement, but the relay contacts are a precious metal and there is only about 2 Amps going to the regulator and that is only when the battery voltage is low and the regulator is trying to charge it up so it doesn't matter.

If your regulator regulates to 14.5 Volts, then that is what the battery voltage will be, but check that it is. Stock relay type regulators have a tendency to go high with a light load when they get hot so this mod will work best with a solid state regulator.

Not only will this arrangement prolong the battery life, it will also do the same for the alternator rotor because the alternator will no longer be producing that extra .5 to 1 Volt to the battery so the current to the rotor from the regulator will be less, resulting in a cooler rotor.

DOWNSIDE: If the battery goes below 9 Volts, the relay may not energize so even if you kick start the engine, the alternator will not recharge the battery. Just be aware of that possibility and check for charging under those circumstances.

I have a circuit to warn you of a no charge condition and I'll post it next.

 

[pamcopete]

White Light...ning,

Here is a cute little circuit that will make your headlight white fault light also work as a charge / no charge indicator. Basically it just uses the safety relay to turn on the white light if the alternator is not charging for any reason.

 

[wingman1946]

I have had enough wiring for a while but this does look pretty cute.

 

[Tombo14300]

Been trying to find some of these screws butt my local hardware stores dont carry them. Seen some on ebay but they are nylon plastic.. i know plastic melts but its this still what i want? The nylon plastic?

 

[toomuchstuff]

A good source for the nylon screws for those who can't find them locally is McMaster Carr. https://www.mcmaster.com They stock them in hex head and phillips head.

 

[CC1]

Wingman1946 asked that I try to clarify and simplify the "Three Nylon Screw Mod", so we'll give it a go.

I've not done this mod, and have no plans to do so, but understand the procedure.

This mod was cooked up long ago by other members, and is intended for one specific application scenario:
Modifying a B-type 70-79 alternator to allow the use of later A-type 80-on combined solid-state regulator/rectifier.
Other combined rec/regs may be used, if they are the A-type, which provide a regulated grounding for a powered exciter/rotor.

Reference threads for this mod:

http://www.xs650.com/forum/showthread.php?t=4170
http://www.xs650.com/forum/showthread.php?t=6477
http://www.xs650.com/forum/showthread.php?t=11947
http://www.xs650.com/forum/showthread.php?t=18358
http://www.xs650.com/forum/showthread.php?t=38428
http://www.xs650.com/forum/showthread.php?t=41778
http://www.xs650.com/forum/showpost.php?p=418291&postcount=10

The B-type 70-79 alternators rotor brush configuration:
Regulated power (green wire) is supplied to the outside brush.
The inside brush is grounded through the case screws.

The A-type 80-up alternators rotor brush configuration:
Regulated ground (green wire) is supplied to the outside brush.
The inside brush is powered by switched power (brown wire).

To achieve this, the alternators have these differences:
The alternator cases have different brush block mounts.
The brush blocks have a different screw hole above the inner brush.
The inner brushes have different hold-down brackets.
The wiring lugs to the inner brush go to different screws.

An outside view of the two different brush block configurations:
View attachment 54790

An inside view of the two different brush block configurations:
View attachment 54791


Two styles of regulators exist, and must be properly matched to the respective alternator.
- "B" type regulator that supplies power to a grounded rotor must be used with a 70-79 alternator configuration.
- "A" type regulator that grounds a powered rotor must be used with a 80-up alternator configuration.
View attachment 140355

This mod allows the use of the later style A-type grounding regulators on a 70-79 alternator.

First, replace the three M4x0.7-12mm steel screws that ground the inner brush with:
Three M4x0.7-12mm Nylon screws that will float/isolate/unground the inner brush.

Next, the black wire that originally went to ground on the inside brush must be supplied switched power by splicing it to a switched power (brown wire).

The original first method is to cut the black wire on the main harness side of the alternator connector, leaving about a 2 inch pigtail, to which a brown extension wire may be soldered and then spliced into the brown wire (switched power) of the new rec/reg.


Another second method that may be easier, is to cut and splice the black wire near where it connects to the regulator connector.

This is my old 1971 XS1B main harness, uncovered to reveal that the black wire simply connects the regulator and alternator brush. There is NO additional connection to this wire. It is independant, and NOT grounded. Grounding for this wire is provided by the inner brush's mounting screws.

As such, once the black wire is cut, the rest of the wire that goes to the old regulator connector is NOT grounded. That end of the black wire must be grounded, or spliced to another grounded black wire, if you expect to get ground at that connector.

View attachment 58973

A close up of the black wire and the two possible locations for cutting and splicing.

View attachment 58974

This regulator connector location (on a 71 XS1B, thanx Angus!) is much easier to access, and conveniently near a brown wire.

View attachment 58975

However, this second method needs to be confirmed, as the black wire may attach to a grounding point within later 72-on main harnesses. A simple test would be to disconnect the black wire at the inner brush, unplug the regulator, then test for continuity of the black wire to ground...

Wingman1946 asked that I try to clarify and simplify the "Three Nylon Screw Mod", so we'll give it a go.

I've not done this mod, and have no plans to do so, but understand the procedure.

This mod was cooked up long ago by other members, and is intended for one specific application scenario:
Modifying a B-type 70-79 alternator to allow the use of later A-type 80-on combined solid-state regulator/rectifier.
Other combined rec/regs may be used, if they are the A-type, which provide a regulated grounding for a powered exciter/rotor.

Reference threads for this mod:

http://www.xs650.com/forum/showthread.php?t=4170
http://www.xs650.com/forum/showthread.php?t=6477
http://www.xs650.com/forum/showthread.php?t=11947
http://www.xs650.com/forum/showthread.php?t=18358
http://www.xs650.com/forum/showthread.php?t=38428
http://www.xs650.com/forum/showthread.php?t=41778
http://www.xs650.com/forum/showpost.php?p=418291&postcount=10

The B-type 70-79 alternators rotor brush configuration:
Regulated power (green wire) is supplied to the outside brush.
The inside brush is grounded through the case screws.

The A-type 80-up alternators rotor brush configuration:
Regulated ground (green wire) is supplied to the outside brush.
The inside brush is powered by switched power (brown wire).

To achieve this, the alternators have these differences:
The alternator cases have different brush block mounts.
The brush blocks have a different screw hole above the inner brush.
The inner brushes have different hold-down brackets.
The wiring lugs to the inner brush go to different screws.

An outside view of the two different brush block configurations:
View attachment 54790

An inside view of the two different brush block configurations:
View attachment 54791


Two styles of regulators exist, and must be properly matched to the respective alternator.
- "B" type regulator that supplies power to a grounded rotor must be used with a 70-79 alternator configuration.
- "A" type regulator that grounds a powered rotor must be used with a 80-up alternator configuration.
View attachment 140355

This mod allows the use of the later style A-type grounding regulators on a 70-79 alternator.

First, replace the three M4x0.7-12mm steel screws that ground the inner brush with:
Three M4x0.7-12mm Nylon screws that will float/isolate/unground the inner brush.

Next, the black wire that originally went to ground on the inside brush must be supplied switched power by splicing it to a switched power (brown wire).

The original first method is to cut the black wire on the main harness side of the alternator connector, leaving about a 2 inch pigtail, to which a brown extension wire may be soldered and then spliced into the brown wire (switched power) of the new rec/reg.


Another second method that may be easier, is to cut and splice the black wire near where it connects to the regulator connector.

This is my old 1971 XS1B main harness, uncovered to reveal that the black wire simply connects the regulator and alternator brush. There is NO additional connection to this wire. It is independant, and NOT grounded. Grounding for this wire is provided by the inner brush's mounting screws.

As such, once the black wire is cut, the rest of the wire that goes to the old regulator connector is NOT grounded. That end of the black wire must be grounded, or spliced to another grounded black wire, if you expect to get ground at that connector.

View attachment 58973

A close up of the black wire and the two possible locations for cutting and splicing.

View attachment 58974

This regulator connector location (on a 71 XS1B, thanx Angus!) is much easier to access, and conveniently near a brown wire.

View attachment 58975

However, this second method needs to be confirmed, as the black wire may attach to a grounding point within later 72-on main harnesses. A simple test would be to disconnect the black wire at the inner brush, unplug the regulator, then test for continuity of the black wire to ground...

Hey XS1Bs
I've got my alternator cover off doing some repairs and I will be doing the nylon screw, reg/rectifier mod a littler later but for now I'm going to go ahead and install the nylon screws and unearth the brushes. That picture you posted here showing which metal screws to replace with nylons, that's correct right? I'm gonna go off of the picture for now and finish up the rest of the wiring later. Thanks (1971 model engine and charging system)