Your inner brush looks strange. It looks like an outer brush was installed over the framework of an original inner brush. Here's a pic of the outer and inner brushes. Note the larger bracket on the inner brush, held in place by 3 screws .....

View attachment 235248

I don't know, maybe what you've got will work fine, but maybe not. Maybe the brush isn't getting grounded as well as it should (it grounds through the 3 screws). Maybe that's why your slap test is weak. You might want to get yourself an actual inner brush.

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Well spotted ..
If I get this right it has now been tested with 2 regulators

Dead regulator? Was leant one by a mate to substitute in and I think it was dead. ( Green windings beside it got really hot after only a few seconds in place, was quick to remove it. )

I would be careful jumping and sort out the brushes first Since the Regulator already jumps it if I remember it correctly.
( Bricks at 5 o clock shorts connection until it starts charging )

?? Taking out the Brushes And plug in and out the regulator Measure at brown and green ..perhaps

1675849704838.png
 
The rotor only draws about 2-2.5 amps of current. Provided the screws are tight and the metal clean, a single screw is plenty of ground surface.
Yeah, with the cover on the pull is pretty weak. Don't recall for sure but I think that was about a 0.010" feeler in the video... and yeah, it barely pulls it.

If your meter has a 10 amp function, plug the pos test lead into the brown wire (regulator still disconnected) and the neg lead into the green wire. Turn the key on, verify the slap and look at the meter. Current draw should be about 2 to 2.5 amps. If it is, the rotor and ground are good.
 
Amps:
With reg disconnect between brown and green we get 4.05A.
From what you’re saying that’s double what it should be? Does this suggest rotor is bad in spite of the rings measurements being good?

Brushes:

I Have three options. I like option2.
1 leave as is- very likely contacts are ok
2 Reverse the layers and reinstall, maybe resulting in a little better contact( see attached photos). If I layer them with the small bracket under the larger one surely there’s enough contact?
3. Unsolder the ones I have and resolder them back onto the original larger plate creating the correct configuration. Just consider I have the gear, flux etc to solder but the technique may be another thing.
Happy to follow the consensus and to do the solder if necessary.

Currently reinstalled to config 2.

Oh yeah. Slap test is so weak that when I put the cover back on and use 0.15, as per video, there’s nothing.

In Summary:
Looks like we are back at page one.
Negative slap test and a rotor that is drawing 4 amps instead of your desired 2 amps.
New Rotor? What the heck I’m running out of parts to replace. 😂( Hence the record breaking).
 

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First... your brushes are fine the way they are in my opinion. I'd let 'em be.

Yes, 4 amps is way too much. Based on my experience rebuilding rotors, yours appears to be shot. In some cases they'll ohm good... or somewheres close, but when you shoot some power into 'em the insulation breaks down and you'll get small shorts across the windings. that draws more current but since we're jumping coil windings, magnetism decreases. At least, that's how it looks from this armchair.

Iirc, there's a guy over in Oz that rewinds 'em. Can't remember who though. @Signal , you remember who it is... or have I been hittin' the pipe too much again?
 
First... your brushes are fine the way they are in my opinion. I'd let 'em be.

Yes, 4 amps is way too much. Based on my experience rebuilding rotors, yours appears to be shot. In some cases they'll ohm good... or somewheres close, but when you shoot some power into 'em the insulation breaks down and you'll get small shorts across the windings. that draws more current but since we're jumping coil windings, magnetism decreases. At least, that's how it looks from this armchair.

Iirc, there's a guy over in Oz that rewinds 'em. Can't remember who though. @Signal , you remember who it is... or have I been hittin' the pipe too much again?
Ok so new rotor time it is. Might be able to get one in the weekend with a 3 hour round trip. Off to India next week for a month so keen to get it sorted by then. 🤞🏻.

STOP PRESS
Picking up second hand one from a guy in the XS650 club racing team in 8 hours or so. Will install and start the process all over. 👍🏻🤞🏻🤭
 
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I've no experience with Ricks Rotors. Anyone?
 
I have one that has had no issues - from before I joined here and found Rewinds by Jim:)
 
Sorry, I have no clue about an Aussie rotor rewinder. I thought you were the only part time rotor winder in existence.
 
Thanks Kev. For $185.00 AUD I can get a new one. Probably a “Ricks” one but have asked seller if this is the case. Any idea if the Ricks Motorsport ones are any good. Review numbers look OK.

I have to protest but it is Your call your Money Your Problem

The facts are
a) The Brushes are not " Stock" # 39 5T
b ) You have 4 amps Going through the rotor unless shorted before . it ca 2 x Nominal
c ) Measured resistance at the slip rings rotor checks out.

Yes the rotor can short under load it can be heat dependent entirely possible
There is a risk you install the brand new $185.00 AUD Rotor put back the other parts and switch the power on -- Giving the new rotor also 2 x the nominal current and fry it within minutes.

Worst case you trash the Rotor in there with the puller unless you buy a special one
https://yambits.co.uk/xs650-flywheel-puller-p-40106.html

Then you trash the new one upon power on And will be looking for a third one 3 x $185.00 AUD plus work

I sometimes try to repair HiFi say you replace the output transistors without checking other components around esp Emitter resistors
Power up then the new Outputs fry

This i what I mean with the CSF Rule --Cheapest simplest first. Looking at the pictures the Brushes are about half worn already and Dodgy

More measurements on the rotor first ??
Heating it with a warm air gun
Run it and then measure

But the slap test appears to fail ,cold also ..Why does it not show on slip ring Resistance measurement ??
 
You have a 4th option for that inner brush - buy the right one, lol. I like to use original brushes. I think they're made better and last longer. They come up on eBay all the time and can usually be found for the same price as aftermarket ones so I see no reason to use the repops.

Like you, I was reluctant to change out my original mechanical regulator too. That is, until I installed means to monitor the charging output. That showed me that the output on that old mechanical unit was very erratic. At cruising speeds, say in the 3500 to 4K rpm range, when it should have been giving it's full output, the charging would often drop off. All I can figure is the bike's vibrations were messing with the points inside the regulator. I also figured this had to be working the rotor harder than need be, all that constant, unnecessary ramping up and down of the charging output. So, I installed an automotive VR115, and it works great. The charging output is very steady now and doesn't ramp up and down like it used to. And as an added bonus, this regulator truly regulates. After riding a few miles and replenishing the battery charge (reduced by electric starting), this regulator reduces the charging output a bit.

Now yes, I suppose the VR115 is considered "solid state", but it's certainly not a new design. It's for AMC cars and Jeeps from the early '70's .....

https://partshawk.com/standard-motor-products-vr-115-voltage-regulator.html
 
I appreciate all the input. Am confident the brushes are not an issue. They are very little worn, and as I said before I’m happy to solder them into the format of original. My parts source for these is a 3 hour drive round trip. Not sure why I have 3 sets of the wrong ones but as you can see still have the original bracket off an earlier set. I now have the right hand brushes bracket under the original bracket with full contact of brackets and the screw to create the electrical contact.

I like to use original parts too. Very occasionally the practicality can outway the availability. In this case I’ve been using the same brushes and set up for years without issue. Hard to believe a genie suddenly left the bottle.

I picked up two rotors last night. The guy with them had 3 but tested one as being dead. Other 2 good.

Just come up from the dungeon after replacing the rotor. Yes, I have the special rotor puller tool - makes like so much easier.
No change in voltage at battery when @3000RPM. Below is the process including 600 grit wet and dry with contact cleaner to clean up rings.
I could look to redo all the tests but suspect there will be no change.
I like the cheapest simplest philosophy. Right now any permanent solution will be welcome.

Think I’ll quadruple check the slip ring resistances again and let you know.
 

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Change in slap test? Did you re-check current draw on the new rotor?
 
So the old rotor was drawing too much current, this one isn't drawing enough.
 
So the old rotor was drawing too much current, this one isn't drawing enough.
Assuming both rotors have the correct resistance
and brushes is OK ( Which is doubtful ) ground OK

It can only be the Regulator green output at standstill that differs
As I see it.

1675993109225.png
 
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