961 Clutch ?

NikolI, you’ll sell 3 or 4 if you’re lucky.

You’re just gonna cause yourself a ton of stress and aggravation for naught IMHO.

Personally I don’t agree For the following reasons:
As far as I know there have been at least 3 rivet failures in the last year. Prior to that some were fixed by the factory under warranty, so it’s not a new issue. Currently on Stu‘s Facebook 961 page there is one owner with a destroyed basket Due to rivet failure.
Many 961’s currently have very low mileage on the clock So the issue has not become apparent to those yet and once it does the owners will not be able to send the bike back to the factory for a replacement or possibly even buy a replacement from Norton.
Guesstimates suggest around 1000 961’s were produced, so even if only 5% fail …
 
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Not saying they don’t fail Cliffa.

If Nikoli is happy to carry the stock for years then I agree he’ll sell a few eventually.

I just don’t see many coughing up for a costly special clutch assembly in a hurry…
 
So are we saying this is a worthwhile mod to make prior to waiting for a possible failure.
 
Speaking from my own experience, it gets a lot noisier. That's the main reason I pulled mine down to check.

Ken

And therein lies the difficulty IMHO cos they all make a very wrong sounding racket from the primary. So it’ll take a sensitive ear to detect when the normal rattle becomes abnormal.

This will lead to failures going undetected by many owners until it fails catastrophically. It’ll also lead to other owners stripping theirs to find all is well.

Mine made me bloody paranoid !
 
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Why not approach CNW and instead of doing it yourself let them pay you a licence fee per sale, if there is a real market they will sell it easily, you get a share.

I think that’s Nikoli’s best option rather than dealing with individual retail orders.

cNw, one 07, Thiel Motorsports, S.Bodycote are the specialists I can think of, talking to them would get a more accurate feeling for likely interest.

If they took a few each it might be enough to make progress worthwhile?
 
And remember we're not just talking about the rivets there have been spring failures and then there is the matter of pinning the ring gear....

Just wondering about peening the rivets over was this done on a fly press or hydraulic? And thinking about the failures - there obviously was some inspection taking place so what was different between a reliable one and one that failed? Thinking about replacing the rivets; if Norton couldn't get it right with 'experienced' technicians how could you guarantee to get it right if you were remanufacturing them? This makes the TIG weld sound attractive.

If you could do a rivet fix/ spring replace and ring gear pin service I think you would struggle to get many orders if it was much over £300.
 
And remember we're not just talking about the rivets there have been spring failures and then there is the matter of pinning the ring gear....

Just wondering about peening the rivets over was this done on a fly press or hydraulic? And thinking about the failures - there obviously was some inspection taking place so what was different between a reliable one and one that failed? Thinking about replacing the rivets; if Norton couldn't get it right with 'experienced' technicians how could you guarantee to get it right if you were remanufacturing them? This makes the TIG weld sound attractive.

If you could do a rivet fix/ spring replace and ring gear pin service I think you would struggle to get many orders if it was much over £300.
See my reply on the previous page chap.
Regards springs, Ive not seen any fail for sometime....I cant remember if they changed supplier, but I could do some digging. Did any springs fail, without being a causal from failed rivets? The ring gears coming loose, has there been any reported from engines built 2017-?
 
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Regards excessive noise from the primary, they also had issues with backlash gear springs failing. So thats a good point to check. Nortons answer was less preload on the backlash secondary mass. I dont know what effect that had regards noise though...
 
Regards excessive noise from the primary, they also had issues with backlash gear springs failing. So thats a good point to check. Nortons answer was less preload on the backlash secondary mass. I dont know what effect that had regards noise though...
Haven't seen any spring failures recently - that's true but if you were carrying out a service you'd want to drop a set of known good ones in especially if someone brought an older one in.

Yes sorry didn't see the manual peening procedure details. 'When I nod me head you hit it son'. Maybe with the white-hot technology of a jig and a fly press there would be better consistency........... If I was looking at the assembly process and considering the loads involved and the implications of a clutch failure I would be considering something a bit more consistent.
 
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If an older one came in, with zero clutch basket issues after a decent mileage, and no concerns found upon removal for closer inspection...I'd certainly consider that as a known good one, and leave alone. Be sods law that you replace the springs, or any other part, and happen upon a faulty part further down the road.
 
I think Richard (BLIGHTYBRIT) had a spring fail which then caused a lot of damage.

A sudden failure, without any real warning IIRC.
 
Rich's is pretty old, as he sent me a pic the other day and recognised one of the initials in his engine, AN on his shift mech. I'll have a bit of a dig, see if springs got revised. I know Phil and I rejected a fair few for sloppy fit when we were in there.
 
If an older one came in, with zero clutch basket issues after a decent mileage, and no concerns found upon removal for closer inspection...I'd certainly consider that as a known good one, and leave alone. Be sods law that you replace the springs, or any other part, and happen upon a faulty part further down the road.

I suppose it comes down to being 100% confident on your mods.


Hit it again son, I've seen how Clive rides........

961 Clutch ?
 
The fact that we've got some out there, on old revision parts, high miles and no problems, but then some random ones that fail early on...leads me to believe its more of an assembly fuck up than a design or parts concern.
 


6 Springs.
This clutch was built in October 2010 when the engine was still at pre-production.
There was always a 6 spring clutch, but unfortunately it was never pursued.
This particular clutch was offered as a solution to use up gears that were incorrectly ordered in large quantity.
 
The offending broken spring , that damaged the balence shaft & ring gear at 16,300 miles , also 3rd & 4th gear damaged
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I'm of the opinion that there is a clutch out there from an existing bike that could easily be modified to fit, be it Honda, Triumph, Ducati or whatever.
 
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