Rear sprocket question

I've had a problem for a while and I'd appreciate some help.
I finally figured out how to attach photos.

A while back I had an experienced shop disassemble and pack the bearing in my rear hub.

When I first took the bike out for a few miles eveything was ok.
Then I heard a scraping noise that I figured out was the chain seriously rubbing the inside of the chain guard.
I tried adjusting everything I could think of and eventually cut out the side of a spair ratty guard I had just so I could at least run it while I figured out the problem.

In looking at the hub I'm starting to wonder if the brake backing plate is too far into the sprocket drum.

I'm also getting a black powder that is coming out of the drum.
I've attached a couple of photos so could someone tell me if it looks ok.
Is it possible for the work that was done on the hub has allowed this to happen.
Maybe a spacer washer inside the drum missing?

Thanks in advance.
Bob

I think this is the washer you are thinking of sitting on the dummy axle. There is a thin smear of grease under it. It's pretty thin and easily forgotten or lost. Wouldn't take much to pull the rear wheel and take a look. Easily said from here. :mrgreen:

My money is on the bearing retainer circlip having come off the brake drum - if the double-row bearing isn't positively located this is what happens - DAMHIK
The Norton Service notes mention this issue, and the workshop manual specifically mentions fitting the circlip with the 'sharp edge' face outwards - otherwise I'm guessing the circlip can climb out of the groove.

Thanks guys.

I suspect the washer looks too thin to be causing the problem and it's probably the circlip.

I'll take it apart and take a look.

Bob

B+Bogus said:

My money is on the bearing retainer circlip having come off the brake drum - if the double-row bearing isn't positively located this is what happens - DAMHIK
The Norton Service notes mention this issue, and the workshop manual specifically mentions fitting the circlip with the 'sharp edge' face outwards - otherwise I'm guessing the circlip can climb out of the groove.

Click to expand...

Good call. I took it apart tonight and the circlip wasn't in it's groove so drum is moving towards chain side.
Brake drum roughed up pretty bad so I will see if getting it turned will work.
Now at least I won't have any more chain guard rubbing.

Thanks
Bob

B+Bogus said:

My money is on the bearing retainer circlip having come off the brake drum - if the double-row bearing isn't positively located this is what happens - DAMHIK
The Norton Service notes mention this issue, and the workshop manual specifically mentions fitting the circlip with the 'sharp edge' face outwards - otherwise I'm guessing the circlip can climb out of the groove.

Click to expand...

It looks like when the bearing was driven in the metal washer that goes on the felt washer on the dummy axel was not seated into its hole.
It was deformed.
The bearing couldn't be pushed in far enough to get a good enough exposure of the circlip slot.
I'm guessing the circlip didn't seat enough, came out and caused drum to move to chain side.
Drum pretty badly scored.

It is very important that the dummy axel felt retaining washer be tapped into its hole. I know this because when I first reinstalled the bearing it wouldn't seat far enough down and the circlip wouldn't go in, just like what caused problem. Washer moved during driving of bearing.

Next time I tapped felt washer into hole then bearing driven in fine, circlip in and bike ready to go on road tomorrow.

Thanks for the help.

Bob