Shearing rotors

[Litlratt]

Need some help as I am at a loss for a fix.
2005 Ridgeback
The sprocket shaft nut backed off and destroyed stator and rotor.
Cleaned up the mess and replaced the stator and rotor with the improved 32 amp stator and rotor. It was charging as it should but I could feel and hear something dragging from that area. Within a couple of miles, it quit charging.
Took it apart and the lugs on the rotor had been sheared.
Once again, replaced the stator and rotor. No telltale signs of a problem on the innor or outer primary or on the rotor, other than the missing lugs.
Went for a ride and within 5 miles started hearing and feeling the dragging again. Stopped charging before I got home. The dragging also stopped at the time it quit charging.
Sheared the lugs on that rotor too.
I don't know what to do next. Any help in troubleshooting this issue will be greatly appreciated.

 

[Jersey Big Mike]

Ok, let's begin
Was any work done on the bike BEFORE this issue occurred?
When you say sprocket shaft nut backed off on the clutch or the engine?
The ROTOR is part of the brake system, so exactly what are you referring to. Do you mean the flanged hub in the clutch?
Pictures would help us help you.
I'm not trying to pick on you but for us to help, we need to maek sure we are all using the same terms for the same objects.
Do you have the service manual? Someone will post the dropbox link for it I'm sure.
Did you clean the engine nut/threads and lock it with red loctite and 80ft/lbs of torque?
Did you mess with the clutch hub nut? Did you clean the nut and threads and use red loctite to 150ft/lbs (left hand thread)

 

[Litlratt]

Ok, let's begin
Was any work done on the bike BEFORE this issue occurred?
When you say sprocket shaft nut backed off on the clutch or the engine?
The ROTOR is part of the brake system, so exactly what are you referring to. Do you mean the flanged hub in the clutch?
Pictures would help us help you.
I'm not trying to pick on you but for us to help, we need to maek sure we are all using the same terms for the same objects.
Do you have the service manual? Someone will post the dropbox link for it I'm sure.
Did you clean the engine nut/threads and lock it with red loctite and 80ft/lbs of torque?
Did you mess with the clutch hub nut? Did you clean the nut and threads and use red loctite to 150ft/lbs (left hand thread)

The engine sprocket shaft nut backed off because I relied on a Dewalt impact driver to torque it. Clutch hub nut should be 80ft/lbs, engine sprocket nut is 150 to 165ft/lbs.
The nut did not back off on the 2nd and 3rd sprocket/rotor. It was torqued to 160 ft/lbs.

 

[SKOGDOG]

I had the same thing (loose nut wrecked rotor and stator) happen with an open primary on my K9. Took the whole shebang off and went back to OEM. It seems one way the spline could shear off the teeth on the rotor would be if there was play. You seem to know what you’re doing, so no doubt the rotor was seated properly.
Another cause could be drag on the rotor itself. Did you inspect the rotorto see if it’s dragging against anything? If that happened, it would leave a friction mark, esp if it were severe enough for you to sense it as described and to shear the teeth off the rotor. I seem to dimly recall a post citing that a surface of the primary had to be ground down just a bit to accommodate a new and larger charging system. Sorry to not be more specific.
btw: clean the threads with a wire brush on a drill and inside the nut too (pistol bore brush and drill). Brake cleaner and generous red loctite, torque and let it set up overnight. Oh…if you’re picky, you may want to replace the nut..it’s had a hard life. 165+ ft lbs on several occasions can stress threads, so I’ve been told.
p.s. Where in IN are you? I worked in Gary for several years and went to Ball State.

 

[Litlratt]

Yes, always clean and reapply red loctite.
No visible damage on any surface, other than the sheared lugs.
The surfaces on the primary were relieved by a previous owner. Second and third rotor appeared to fit well prior to installing.
The scraping/dragging was intermittent and did not occur at a given rpm or gear.
I'm in Terre Haute, Gary is practically another country.

 

[SKOGDOG]

Outside of excess play or dragging, I’m pretty much coming up dry—please keep us posted on what you find out—inquiring minds want to know!!
Gary is certainly another world away from southern Indiana!!! Haha

 

[Litlratt]

Found another rotor on ebay, it will be here Monday.
In preparation for it I flushed the primary and removed the rotor.
Once again, no physical damage other than the sheared lugs. However, I did notice some discoloration on the inside of the rotor adjacent to the stator, it was copper colored and all the way around.
Checked the second rotor and it was the same way.
This suggested to me that the rotor was being crushed into the stator.
Going against the explicit instructions for my make and model, I put the small spacer that came with the kit between the stator and the rotor. Replaced the sprocket and torqued it to 160.
I did not put the outer primary back on as I wanted to watch the rotor while it was running. It spun freely and appeared to be in time with the sprocket.
So, put the outer primary back on, some fresh oil and went riding. Rode for about 5 hours around town today. Digital voltmeter was at 13.7 most of the time. This was with a rotor that did not have any lugs. Only the pressure from being pinched between the sprocket and the spacer.
I'll replace the rotor Monday with the new one and use the spacer.
Any bets on the outcome?

 

[Litlratt]

Double post

 

[SKOGDOG]

Congrats! Glad you figured it out Lilratt. Thanks for letting us know. Sorry that faulty instructions had you buying rotors—they are not cheap.

 

[Mickmorris]

I’ve been following this thread. Glad you got it figured out. A picture of what you are dealing with would be awesome. I guess I am confused about the lugs that are sheared off. Below is a photo of the stator/rotor? for a 2000 Vintage Sport. Curious as to what these parts looks like off of a’05 ridgeback. Trying to understand what happened in case I ever run across this issue in the future. Thanks
Mick

 

[Litlratt]

The lack of lugs is obvious.
The copper residue from the windings on the stator, by coincidence, follows the path of the 2 holes.

 

[Mickmorris]

The lack of lugs is obvious.
The copper residue from the windings on the stator, by coincidence, follows the path of the 2 holes.

Ahh lugs/teeth for the splines. Thanks for clarifying. I was literally scratching my head on that. So I assume this is the washer you are referring to that wasn’t put on initially. And caused your problem.

 

[Litlratt]

Ahh lugs/teeth for the splines. Thanks for clarifying. I was literally scratching my head on that. So I assume this is the washer you are referring to that wasn’t put on initially. And caused your problem. View attachment 125957

Yes

 

[Mickmorris]

Yes

Right on Brother. Glad you got it sorted out!

 

[john sachs]

Another thing I used to do, was to weld a large O.D. flat washer, on the outside of the rotor spline area, 1/8" thick, with an I.D., that just slipped over the o.d. of the splines of the rotor. Saved a lot of rotors from rounding out the splines.
John

 

[Litlratt]

Received and installed the new rotor, with the small spacer, today.
All is as it should be.
Thank you all for your help.

 

[Litlratt]

Just talked to Donna and she assured me they, bigdogpartskingpin, would make it right.