Brake drum/plate 1974 Mk2a

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Hello all, When I recently re-tightened the rear wheel spindle the wheel locked tight. I put this down to a missing bearing spacer which was duly purchased and fitted. This stopped the locking up issue but now I have a nasty click/clunk noise coming from the drum/plate area when the wheel is rotated.

The dummy axle is loose and wobbly and the whole setup seems unstable. I've stripped it down and it seems that everything that should be there is, according to the parts book. Am I correct in thinking that there is only a felt washer and felt retaining washer between the dummy axle and bearing? I'm assuming there must be some play to allow it to spin freely.

There were rub marks on the ends of the cush drive paddles inside the drum (I've dressed these as the were a little sharp). There are also rub marks on the metal parts of the brake shoes with witness marks near the outer edge of the drum. I have tried using the correct spacing washers on the plate but to no avail. I have also noticed that the correct size spacer between the speedo drive and swingarm is too long so I have made a shorter one to suit.

I'm sure that these issues are related and I've made a "schoolboy error" somewhere. I just can't see what. I've (hopefully) attached a few photos so you can see.

Any thoughts would be gratefully appreciated. Thanks............Shaun.

Spacer

Hub

Plate & Shoes

Drum

As a very new Norton owner I…

As a very new Norton owner I’m not really qualified to answer fully. However I have just removed and replaced the rear wheel, stripping the brake drum down for investigation and cleaning during my recommissioning of the bike. I noticed exactly the same as you, eg a wobble. All of that disappeared once the axle was screwed into the hub when I refitted the wheel. All of the bearings and seals etc. were perfectly fine. I assume it is “they’re all like that guv”

Have you looked at the…

Have you looked at the exploded drawing here?

https://andover-norton.co.uk/en/shop-drawing/178/rear-wheel-drum-bearings

e.g. I wonder if part 47 circlip might be missing? or bearing spacer 23?

Shoes rubbing on the brake…

Shoes rubbing on the brake drum - from the marks on the back of the drum and the edge of the leading shoe. The sprocket looks knackered too. The stub axle, the one in the drum, doesn't look right - looks like it's made from several parts. You do know there's spacer between the brake plate and the swinging arm? And why are there two washers on the spindle outside the swinging arm offside.

Think you need to find someone with a properly assembled wheel and compare.

As Stan said, drum is scrap,…

As Stan said, drum is scrap,possibly chain too, don't buy new from internet, only Norton.The shoes may be poor pattern, And anyway need swapping round as thicker shoe lining needs to be the leading one.Take care installing speedo drive to engage tounge into slot. Also center brake before tightening axle.My chain and sprockets hardly wear, but then I don't use chain wax, only Linklife and brushed on ep90. A scottoiler is good too.

brake shoe plate and drum gap

Hi All,

i am re building a 850 MK2 commando and the gap between the brake drum and shoe plate seem excessive.

this bike has been a nightmare as many parts don't look right. in the drum the baring was single row not double so the brake shoe sides were scraping on the drum

I renewed this with the correct double row baring and now the gap between the drum and the shoe plate edge seem larger than it needs to be also when I try to fit the spacer between the speedo drive and swinging arm the gap seem to be about 5 to 6 mm to small. it seems like the drum needs to go to the left by about 5mm

any advice would be much appreciated

Attachments

hub 2.jpg

hub1.jpg