Knocking / rattling inside primary drive case + backfire

Brake cable failure can lead to very nasty crashes out on the road. There is a safety spring available from most fine Norton suppliers to prevent/reduce risk of brake lever dropping into pavement if cable fails. Bit of a Chinese puzzle to fit that spring but i'll have a look for some pics I have of it.
Here's my previous post in older thread showing spring installed:

Post in thread 'Rear Brake lever spring' https://www.accessnorton.com/NortonCommando/rear-brake-lever-spring.27403/post-413609
 
Muchos Gracias

I actually already have that spring, but hadn’t got around to fitting it. I now feel significantly more motivated to fit it! 😁
 
I used both tab washer, and loctite.

Unfortunately (or probably fortunately) I just snapped the rear brake cable, while applying pressure to torque the rotor nut to 70ft lb. I’ll order a replacement on Monday, together with another set of stator studs. I replaced these already, and just tried the stator on them but no go. One must be bent. I’ve still got the old ones, so I’ll have a play to find a set that works.

On the plus side, the clutch is in (I shimmed and chain alignment is spot on now). The new woodruff keys are a great fit too.
What torque did you do the clutch center nut too ?
I'd not go above 40ft lb if using a tab washer
The reason people don't use the tab washer is because it is mild steel
And if done to recommend torque the nut will eat through the tab washer allowing the clutch center to become loose on its spline wearing away the clutch center without the hapless owner realising
The next time he delves into the clutch he finds the nut loose and the clutch center loose (if he's lucky)
He thinks to himself it's a good job that tab washer was there or that nut would have come completely off
 
The reason people don't use the tab washer is because it is mild steel
And if done to recommend torque the nut will eat through the tab washer allowing the clutch center to become loose on its spline wearing away the clutch center without the hapless owner realising
Only if part 06.3447 is not installed. You put on the tab washer, then 06.3447, then the nut. The nut never touches the tab washer.
 
I went for 45ft lb. I have the stronger circlip, so figured it could take it. Washer 06.3447 was used. I also used loctite.
 
By the way - given how much I’ve done to the primary, and how many things I’ve changed, I intend to split it again for a full inspection after 500 miles to check that everything is still good.
 
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I went for 45ft lb. I have the stronger circlip, so figured it could take it. Washer 06.3447 was used. I also used loctite.
You're way more than fine. I use the standard circlip (they are enough of a PITA to suit me), tab washer, fixing washer, no locktite, and 50 ft lb. In truth, as long as the nut doesn't loosen, just about any torque would work - it's a splined shaft!

Until I read the Old Britts warning, I always used 70 ft lb without trouble, so I don't know if there is an actual problem. I do use a new circlip each time.
 
By the way - given how much I’ve done to the primary, and how many things I’ve changed, I intend to split it again for a full inspection after 500 miles to check that everything is still good.
That's good, with all you've done it's probably good to change the oil around then.

Have you started it to see how it sounds now or are you still stuck on the stator? If stuck on the stator, sometimes they are hard to get started but will seat fine. If you have a tapered reamer, a couple of twists on the back side helps them start on without making the holes overall larger - not required, just nice to have.
 
I’m not going to worry about the Dynodave mod for now. But noted for the future, cheers.
If you have access to a lathe, you could make this:

Knocking / rattling inside primary drive case + backfire
Cut 30 mm of the clutch rod, add a 6 mm bearing ball and a +/- 25 mm rod , made out of an old valve stem, or something similar.
( the std rod is a too sloppy fit )
O- ring from an Amal set screw.
The O-ring stays put and the rod slides .
Perfect seal, and is more compact than a DD seal:

Knocking / rattling inside primary drive case + backfire

The felt ring is optional if you run a belt , to keep the tip from running dry.


Knocking / rattling inside primary drive case + backfire
 
That's good, with all you've done it's probably good to change the oil around then.

Have you started it to see how it sounds now or are you still stuck on the stator? If stuck on the stator, sometimes they are hard to get started but will seat fine. If you have a tapered reamer, a couple of twists on the back side helps them start on without making the holes overall larger - not required, just nice to have.
Not started it yet. I didn’t get the rotor nut fully torqued before the brake cable let go. I’m going to have to wait for a new cable, or possibly put something temporary in place to allow me to torque the rotor nut.
 
Not started it yet. I didn’t get the rotor nut fully torqued before the brake cable let go. I’m going to have to wait for a new cable, or possibly put something temporary in place to allow me to torque the rotor nut.
Since you're now a primary expert, you need this tool: https://andover-norton.co.uk/en/shop-details/15502/clutch-locking-tool

WAY better than the rear brake and can also be used for the timing-side main shaft nut and if the primary is together, the nuts inside the timing chest.

When I'm breaking a bike down to rebuild, I lock the clutch with this and loosen the camshaft nut, timing side crank worm gear/nut, rotor nut, clutch nut and if needed the gearbox mainshaft nut on the timing side as the first step.
 
It would normally pass between the carb manifolds and through a grommet and a clip attached to the head steady.
Knocking / rattling inside primary drive case + backfire
@L.A.B. Don't suppose you know the part number for that grommet that goes on the clip? I've been scouring the exploded drawings - can't find it.

EDIT: Guess I can use a generic grommet.
 
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A bit more progress. I’ve completed installing the missing timing scale. Scariest drill & tap that I’ve done for a while. Very little material left to work with. I went as deep as I dared! Worked out nicely, I think. Time will tell (groan).

Knocking / rattling inside primary drive case + backfire


Knocking / rattling inside primary drive case + backfire
 
Less of the loctite red when you come to the big nuts, to undo the nut later you need to heat it a lot higher to break the bond on red than blue or green.
 
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